AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1230 PM EST SUN NOV 12 2006 .AVIATION... MAIN AVIATION CONCERN FOR THIS TAF PACKAGE IS HOW FAST PESKY MVFR STRATOCUMULUS DECK WILL ERODE. STRATOCUMULUS DECK WAS NEARLY STUCK ACRS THE REGION AS A RIDGE OF HIGH PRESSURE FROM THE SFC THROUGH 850 MB WAS PROVIDING FOR FAIRLY LIGHT WIND REGIME THROUGH THE LAYER. AS A RESULT...ONLY DAYTIME SUNSHINE WILL BE THE KEY FACTOR ON DISSIPATING THE DECK. LATEST VISIBLE SATELLITE IMAGERY WAS INDICATING THAT THIS INDEED WAS OCCURRING ACRS THE WEST. WILL ONLY EMPLOY A SCATTERED DECK AT KSBN WITH TAF ISSUANCE. FARTHER EAST...THE EROSION PROCESS HAS BEEN MUCH SLOWER. THEREFORE...WILL HAVE TO FCST A BKN MVFR DECK AT KFWA FOR AT LEAST THROUGH LATE AFTN. FOR TONIGHT...SFC RIDGE OF HIGH PRESSURE WILL MOVE SLOWLY EAST. A WEAK COLD FRONT ACRS THE PLAINS THIS AFTN WILL MOVE INTO THE WRN GREAT LAKES BY LATE MONDAY AFTN. AS THIS FEATURE APPROACHES...MID AND HIGH LVL CLOUDINESS WILL INCREASE. && .PREV DISCUSSION... UPDATE... SATELLITE IMAGERY THIS MORNING CONTINUES TO SHOW PLENTY OF STRATOCUMULUS CLOUDS ACRS THE FCST AREA. LOCAL RAOBS AND RUC40 SOUNDINGS INDICATE THAT THIS MOISTURE LAYER IS NEAR 900 MB...AND IT IS TRAPPED BENEATH A STRONG INVERSION. WITH A RIDGE OF HIGH PRESSURE FCST TO MOVE ACRS THE AREA TODAY...CLOUDS WILL HAVE A HARD TIME EXITING THE REGION AS WINDS WILL BE FAIRLY LIGHT OVERHEAD. AS A RESULT...THE CLEARING OF THE CLOUDS WILL HAVE TO DEPEND ON THE LATE AUTUMN SUNSHINE IN ORDER TO ERODE THE CLOUD DECK. WILL UPDATE THE ZONES/GRIDS TO KEEP MOSTLY CLOUDY CONDITIONS LONGER THROUGH THE DAY...BUT EVENTUALLY HOPING THAT SKIES BECOME PARTLY CLOUDY LATE. WILL ALSO TWEAK HIGH TEMPERATURES DOWN SOME DUE TO THE LINGERING CLOUD COVER. SHORT TERM... SFC HIGH PRESSURE RIDGE EXTENDING FROM NRN MI TO SRN IL AND MOVG SLOWLY EAST THIS MORNING. WIDESPREAD LOW CLOUDS TRAPPED BENEATH INVERSION BASED AROUND 925MB TO THE EAST OF THE RIDGE SHOULD LINGER OVER THE AREA PAST DAYBREAK WITH A GRADUAL CLEARING FROM W-E DURING THE DAY AS THE RIDGE MOVES INTO WRN OH BY 00Z MON. LOWERED MAXES A FEW DEGS FM PREVIOUS FCST IN AGREEMENT WITH COOLER LATEST MAV/MET FCSTS WHICH SEEM REASONABLE GIVEN WK MIXING AND LINGERING LOW CLOUDS AT LEAST PART OF THE DAY. SKIES SHOULD BE MOSTLY CLEAR THIS EVE AND WINDS LIGHT AS THE RIDGE MOVES SLOWLY EAST OF THE AREA. A SHRTWV OVER THE FOUR CORNERS THIS MORNING IS EXPECTED TO LIFT NE TO THE MS VLY BY MON MORNING. THIS WILL INCREASE THE GRADIENT WITH SOME INCREASE IN HIGH CLOUDS LATE OVER WRN PORTIONS OF THE AREA. HWVR, SHOULD BE DECENT RADIATIONAL COOLING EARLY ACROSS THE ENTIRE AREA CONTG SE MOST OF THE NIGHT. MINS AT OR SLIGHTLY BLO MOS SEEM REASONABLE GIVEN THIS EXPECTATION. LONG TERM... MONDAY THROUGH SATURDAY. HIGH PRESSURE WILL SLIDE EAST ON MONDAY. MODELS CONTINUE TO BRING A WEAKENING FRONTAL BOUNDARY ACROSS THE GREAT LAKES...BUT FORCING WILL DECREASE WITH TIME AND WHAT MSTR EXISTS WITH IT WILL REMAIN MAINLY NORTH OF THE AREA. POPS WERE PULLED BY DAY SHIFT AND WILL CONTINUE WITH THIS THINKING AS AT BEST A SPRINKLE OR 2 MAY OCCUR. THEN ATTENTION TURNS TO SYSTEM ADVERTISED TO ARRIVE SOMETIME IN THE TUES NGT/WEDS TIME FRAME. WIDE VARIETY OF SOLUTIONS COMING OUT OF 00Z RUNS BY 12Z WEDS...WITH ECMWF FURTHEST NORTH ACROSS N IL...TO NAM OVER CNTRL IL...GFS OVER W TENNESSEE...AND UKMET OVER N LOUISIANA. ALL SOLUTIONS HAVE MANY IMPLICATIONS ON AMOUNT OF PRECIP AND CONVECTIVE POTENTIAL. GENERAL CONSENSUS OF MOST MODELS HAVING THE LOW TRACK OVER OR SOUTH OF THE AREA WOULD SUGGEST MINIMAL THUNDER CHANCES...BUT INCREASING CHCS FOR MEASURABLE QPF. CURRENTLY HAVE LOW CHC POPS IN FOR TUES EVE THEN HIGH CHC TUES NGT INTO WEDS. WAS TEMPTED TO INCREASE TO LIKELY ON WEDS BUT IF FURTHER SOUTH SOLUTIONS VERIFY...MAIN PRECIP MAY NOT ARRIVE TILL WEDS NGT/THURS SO WILL LEAVE THINGS ALONE. ALL PRECIP THROUGH THURS SHOULD BE IN THE LIQUID FORM...WITH SNOW BECOMING MORE OF AN ISSUE ON THE BACK SIDE OF THE SYSTEM. BY 00Z FRI MODELS DO COME INTO SLIGHTLY BETTER AGREEMENT ON THE SFC LOW SOMEWHERE FROM NE LK HURON TO LAKE ERIE OR NW OHIO. ANOTHER TROUGH WILL MOVE IN ACROSS SOUTHERN CANADA LATE THURS AND ALLOW FOR THE SYSTEM OVER THE GREAT LAKES TO BE PULLED NORTH ENDING PRECIP CHANCES JUST AS THE COLDER AIR ARRIVES. ANOTHER FRONT MAY BE ASSOCIATED WITH THIS APPROACHING TROUGH IN THE FRI TIME FRAME. ENOUGH MODEL ISSUES THAT FAR OUT TO PRECLUDE PRECIP MENTION. IF SCENARIO WORKED OUT WOULD BE SHOT AT SOMEWHAT COLDER AIR ARRIVING WITH THIS FRONT...BUT NOT SO SURE THIS WILL OCCUR. PLENTY OF TIME TO MONITOR SO WILL KEEP THURS NGT THROUGH SATURDAY DRY WITH TEMPS NEAR OR JUST BELOW NORMAL. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ AVIATION/UPDATE...HICKMAN SHORT TERM...TAYLOR LONG TERM...FISHER in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE INDIANAPOLIS IN 1029 AM EST SUN NOV 12 2006 .UPDATE...STRONG 900MB INVERSION STILL HANGING ON OVER INDIANA THIS MORNING. H85 RIDGE MAX IS STILL SLIGHTLY TO OUR WEST WHICH IS CONTRIBUTING TO THE LACK OF CLEARING. RUC SHOWING PLENTY OF MOISTURE BELOW 900MB AND UNTIL THE RIDGE MAX PASSES TO OUR EAST SUBSIDENCE WONT BE STRONG ENOUGH TO FORCE THE INVERSION TO THE GROUND. THE FEW BREAKS IN THE CLOUDS HAVE BEGUN TO FILL IN WHICH WILL ALSO LIMIT DAYTIME HEATING. WITH LITTLE TEMPERATURE ADVECTION BELOW 900MB WOULD NOT EXPECT CLOUDS TO BREAK UP UNTIL THE 18Z-21Z TIMEFRAME. BECAUSE OF THIS WILL SHAVE A DEGREE OR TWO OFF OF DAYTIME HIGHS. UPDATE OUT SHORTLY. && .AVIATION...DISCUSSION FOR 121200Z TAF ISSUANCE. HI PRES CENTERED OVR IL AT 11Z. MVFR CLOUD LINE IS LOCATED ALONG INDIANA ILLINOIS BORDER. SOUNDINGS SHOW STRONG INVERSION PERSISTING UNTIL LATE MORNING/EARLY AFTERNOON WHICH SHOULD KEEP LOW CIGS AROUND UNTIL THEN. 95 PERCENT RH FROM THE NAM AT 925 MB MATCHES UP WELL WITH CURRENT LOW CIGS AND AGREES WITH SOUNDINGS ON TIMING OF VFR. INVERSION SHUD MIX OUT AT ALL SITES BY 17Z AND MIX CIGS TO VFR. && .PREV DISCUSSION...MAIN WEATHER FACTOR TO WORK WITH TODAY WILL BE THE CLOUDS. THIS MORNING SATELLITE PICTURES AND SURFACE OBSERVATIONS SHOW A LINGERING AREA OF LOW CLOUDS OVER MOST OF CENTRAL INDIANA. THESE CLOUDS ARE BEING TRAPPED OVER THE AREA BY AN INVERSION. ONCE THE INVERSION BREAKS MID TO LATE MORNING THE CLOUDS SHOULD MOVE OUT. THE NEXT CLOUD PROBLEM IS AN AREA OF CI THAT IS OVER ILLINOIS MOVING EAST. ONLY THE GFS HAS THIS MOVING INTO INDIANA. WITH ITS PRESENT STEADY MOVEMENT THIS LOOKS GOOD. THE PROBLEM WILL BE WHEN IT DOES MOVE IN HOW DENSE WILL IT BE. AT THE PRESENT TIME IT LOOKS THIN ENOUGH TO GO MOSTLY SUNNY. THE CLOUDS DURING THE MORNING WILL SLOW THE TEMPERATURE INCREASE SOME ALONG WITH ANY CLOUDS THIS AFTERNOON. SO WILL GO TOWARD THE LOWER GUIDANCE HIGHS. HIGH PRESSURE WILL CONTINUE TO BUILD INTO INDIANA DURING THE DAY. THE GFS CONTINUES TO SHOW MID AND HIGH LEVEL MOISTURE OVER INDIANA TONIGHT. WILL GO AT LEAST PARTLY CLOUDY DUE TO THE MOISTURE. WITH THE CLOUDS WILL KEEP MIN TEMPERATURES A LITTLE HIGHER. THE HIGH WILL MOVE EAST OF INDIANA ON MONDAY. THIS WILL ALLOW A WEAK COLD FRONT TO MOVE INTO THE STATE. 850 MB TEMPS SHOW A WARM UP FOR PART OF THE DAY. WILL GO NEAR GUIDANCE FORECAST. DUE TO LACK OF MOISTURE WILL NOT MENTION ANY RAIN WITH THIS FRONT. && IND WATCHES/WARNINGS/ADVISORIES...NONE. $$ UPDATE...SALLY AVIATION...CP PUBLIC...HAINES in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 855 AM EST SUN NOV 12 2006 .UPDATE... SATELLITE IMAGERY THIS MORNING CONTINUES TO SHOW PLENTY OF STRATOCUMULUS CLOUDS ACRS THE FCST AREA. LOCAL RAOBS AND RUC40 SOUNDINGS INDICATE THAT THIS MOISTURE LAYER IS NEAR 900 MB...AND IT IS TRAPPED BENEATH A STRONG INVERSION. WITH A RIDGE OF HIGH PRESSURE FCST TO MOVE ACRS THE AREA TODAY...CLOUDS WILL HAVE A HARD TIME EXITING THE REGION AS WINDS WILL BE FAIRLY LIGHT OVERHEAD. AS A RESULT...THE CLEARING OF THE CLOUDS WILL HAVE TO DEPEND ON THE LATE AUTUMN SUNSHINE IN ORDER TO ERODE THE CLOUD DECK. WILL UPDATE THE ZONES/GRIDS TO KEEP MOSTLY CLOUDY CONDITIONS LONGER THROUGH THE DAY...BUT EVENTUALLY HOPING THAT SKIES BECOME PARTLY CLOUDY LATE. WILL ALSO TWEAK HIGH TEMPERATURES DOWN SOME DUE TO THE LINGERING CLOUD COVER. .PREV DISCUSSION... SHORT TERM... SFC HIGH PRESSURE RIDGE EXTENDING FROM NRN MI TO SRN IL AND MOVG SLOWLY EAST THIS MORNING. WIDESPREAD LOW CLOUDS TRAPPED BENEATH INVERSION BASED AROUND 925MB TO THE EAST OF THE RIDGE SHOULD LINGER OVER THE AREA PAST DAYBREAK WITH A GRADUAL CLEARING FROM W-E DURING THE DAY AS THE RIDGE MOVES INTO WRN OH BY 00Z MON. LOWERED MAXES A FEW DEGS FM PREVIOUS FCST IN AGREEMENT WITH COOLER LATEST MAV/MET FCSTS WHICH SEEM REASONABLE GIVEN WK MIXING AND LINGERING LOW CLOUDS AT LEAST PART OF THE DAY. SKIES SHOULD BE MOSTLY CLEAR THIS EVE AND WINDS LIGHT AS THE RIDGE MOVES SLOWLY EAST OF THE AREA. A SHRTWV OVER THE FOUR CORNERS THIS MORNING IS EXPECTED TO LIFT NE TO THE MS VLY BY MON MORNING. THIS WILL INCREASE THE GRADIENT WITH SOME INCREASE IN HIGH CLOUDS LATE OVER WRN PORTIONS OF THE AREA. HWVR, SHOULD BE DECENT RADIATIONAL COOLING EARLY ACROSS THE ENTIRE AREA CONTG SE MOST OF THE NIGHT. MINS AT OR SLIGHTLY BLO MOS SEEM REASONABLE GIVEN THIS EXPECTATION. LONG TERM... MONDAY THROUGH SATURDAY. HIGH PRESSURE WILL SLIDE EAST ON MONDAY. MODELS CONTINUE TO BRING A WEAKENING FRONTAL BOUNDARY ACROSS THE GREAT LAKES...BUT FORCING WILL DECREASE WITH TIME AND WHAT MSTR EXISTS WITH IT WILL REMAIN MAINLY NORTH OF THE AREA. POPS WERE PULLED BY DAY SHIFT AND WILL CONTINUE WITH THIS THINKING AS AT BEST A SPRINKLE OR 2 MAY OCCUR. THEN ATTENTION TURNS TO SYSTEM ADVERTISED TO ARRIVE SOMETIME IN THE TUES NGT/WEDS TIME FRAME. WIDE VARIETY OF SOLUTIONS COMING OUT OF 00Z RUNS BY 12Z WEDS...WITH ECMWF FURTHEST NORTH ACROSS N IL...TO NAM OVER CNTRL IL...GFS OVER W TENNESSEE...AND UKMET OVER N LOUISIANA. ALL SOLUTIONS HAVE MANY IMPLICATIONS ON AMOUNT OF PRECIP AND CONVECTIVE POTENTIAL. GENERAL CONSENSUS OF MOST MODELS HAVING THE LOW TRACK OVER OR SOUTH OF THE AREA WOULD SUGGEST MINIMAL THUNDER CHANCES...BUT INCREASING CHCS FOR MEASURABLE QPF. CURRENTLY HAVE LOW CHC POPS IN FOR TUES EVE THEN HIGH CHC TUES NGT INTO WEDS. WAS TEMPTED TO INCREASE TO LIKELY ON WEDS BUT IF FURTHER SOUTH SOLUTIONS VERIFY...MAIN PRECIP MAY NOT ARRIVE TILL WEDS NGT/THURS SO WILL LEAVE THINGS ALONE. ALL PRECIP THROUGH THURS SHOULD BE IN THE LIQUID FORM...WITH SNOW BECOMING MORE OF AN ISSUE ON THE BACK SIDE OF THE SYSTEM. BY 00Z FRI MODELS DO COME INTO SLIGHTLY BETTER AGREEMENT ON THE SFC LOW SOMEWHERE FROM NE LK HURON TO LAKE ERIE OR NW OHIO. ANOTHER TROUGH WILL MOVE IN ACROSS SOUTHERN CANADA LATE THURS AND ALLOW FOR THE SYSTEM OVER THE GREAT LAKES TO BE PULLED NORTH ENDING PRECIP CHANCES JUST AS THE COLDER AIR ARRIVES. ANOTHER FRONT MAY BE ASSOCIATED WITH THIS APPROACHING TROUGH IN THE FRI TIME FRAME. ENOUGH MODEL ISSUES THAT FAR OUT TO PRECLUDE PRECIP MENTION. IF SCENARIO WORKED OUT WOULD BE SHOT AT SOMEWHAT COLDER AIR ARRIVING WITH THIS FRONT...BUT NOT SO SURE THIS WILL OCCUR. PLENTY OF TIME TO MONITOR SO WILL KEEP THURS NGT THROUGH SATURDAY DRY WITH TEMPS NEAR OR JUST BELOW NORMAL. AVIATION... SFC HIGH PRES RIDGE EXTENDED FROM CENTRAL MI TO SE IL ATTM. LARGE STRATO CU DECK WAS LOCATED EAST OF THE SFC RIDGE. A COUPLE OF LARGE HOLES HAVE DEVELOPED IN THIS DECK OVER LOWER MICHIGAN AND EXPECT THESE WILL EXPAND INTO NRN INDIANA BY 18Z. REMAINDER OF THE PERIOD SHOULD BE GENERALLY CLOUD FREE OTHER THAN SOME PASSING CIRRUS TODAY AND PSBLY A CIRROSTRATUS DECK MOVG INTO THE AREA FROM THE WEST LATE IN THE PERIOD AS A WKNG SHRTWV/CDFNT APPROACHES. DECENT RADIATIONAL COOLING TONIGHT MAY CAUSE TEMPS TO DROP BELOW CROSSOVER TEMP, HOWEVER MIXING SHOULD BE SUFFICIENT TO PREVENT FOG AND DOUBT MOISTURE DEEP ENOUGH FOR STRATUS SO CONTD VFR. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...HICKMAN LONG TERM...FISHER SHORT TERM/AVIATION...TAYLOR in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DODGE CITY KS 305 PM CST SUN NOV 12 2006 .DISCUSSION... DAYS 1-2... THE MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR PRECIP TONIGHT AND TUESDAY AFTERNOON, ALONG WITH TEMPERATURES. THE UPPER TROUGH AXIS THAT WAS OVER THE FOUR CORNERS REGION AT 12Z HAS PROGRESSED INTO COLORADO, AND SHOULD CONTINUE TO MOVE ACROSS THE PLAINS TONIGHT. THE TROUGH HAS BROUGHT PLENTY OF UVV, AND LIGHT ECHOES HAVE SPREAD ACROSS OUR RADAR SCOPE IN THE LAST FEW HOURS. HOWEVER, TEMPERATURE DEWPOINT SPREADS ARE STILL GREATER THAN 20 DEGREES AT THE SFC IN MOST LOCATIONS, AND THE 850MB OBS FROM THIS MORNING SHOW SIMILAR PATHETIC MOISTURE. MOST OF THE ACTIVITY HAS BEEN IN THE MID LEVELS AND LITTLE IF ANY IS REACHING THE GROUND. TEMPS SHOULD BE COOLING OFF TONIGHT THOUGH, AND RUC MODEL SOUNDINGS ARE OPTIMISTIC ABOUT OUR NORTHERN LOCATIONS GETTING ENOUGH MOISTURE IN THE COLUMN FOR SOMETHING TO REACH THE GROUND. WILL KEEP SLIGHT/LOW CHANCE POPS GOING FOR LIGHT RAIN UNTIL MIDNIGHT, WHEN THE TROUGH AXIS AND SFC FRONT SHOULD BE PAST US. CLOUDS SHOULD START TO BREAK UP LATER TONIGHT AS THE TROUGH AXIS MOVES EAST AND SUBSIDENCE SETS IN. WITH THE BREAKS IN CLOUDS, DIMINISHING WINDS, AND LOW DEWPOINTS, LOWS TONIGHT SHOULD DROP DOWN INTO THE UPPER 20S TO LOW 30S. THE LEE SFC TROUGH SHOULD RAPIDLY RE-DEVELOP TOMORROW, WITH SOUTHERLY WINDS. THE MODELS HAVE STRONG RH AT HIGH LEVELS THOUGH, SO SOME CIRRUS AGAIN LOOKS PROBABLE. HIGHS IN THE 50S CONTINUE TO SEEM REASONABLE, SO ONLY MADE MINOR TWEAKS. WINDS SHOULD STAY UP SOME MONDAY NIGHT, KEEPING TEMPS FAIRLY MIXED AND A BIT WARMER THAN TONIGHT. WARMING SHOULD CONTINUE INTO TUESDAY WITH 850MB TEMPS RETURNING INTO THE LOWER TO MID TEENS C. CONTINUED WITH HIGHS IN THE UPPER 50S TO LOW 60S. THE NEXT UPPER TROUGH WILL MOVE OUT INTO THE NORTHERN PLAINS BY TUESDAY, WITH ANOTHER PACIFIC FRONTAL BOUNDARY MOVING INTO THE WESTERN PLAINS BY LATE IN THE DAY. THE LACK OF LOW LEVEL MOISTURE WILL AGAIN BE A FACTOR, SO CONTINUED TO KEEP VERY LOW POPS OF 10- 15 FOR TUESDAY AFTERNOON FOR NOW. DAYS 3-7... FORECAST CHALLENGE THIS PERIOD IS THE EXPECTED SENSIBLE WEATHER FROM A DEEPENING MID-WEEK SYSTEM. BASED ON EXPECTED FORCING FROM THE TROPICS AND RESULTING AMPLIFICATION DOWNSTREAM...THE SYSTEM THAT CURRENTLY IS IN THE NORTHEAST PACIFIC SHOULD DIG INTO THE CENTRAL PLAINS LATE TUESDAY/WEDNESDAY. HOWEVER, EVERYTHING WILL LIKELY BE TOO FAR EAST OF MY CWA TO OFFER MUCH HOPE FOR PCPN. WIND AND BRIEFLY COLDER TEMPS WILL BE IN THE OFFING THOUGH. THEN A QUICK WARMUP IS EXPECTED LATE IN THE WEEK AS HEIGHTS BEGIN TO RISE AGAIN IN RESPONSE TO A FULL LATITUDE TROUGH THAT IS EXPECTED ALONG THE WEST COAST. && .PRELIMINARY POINT TEMPS/POPS... DDC 27 55 36 60 / 20 0 0 10 GCK 26 54 33 61 / 20 0 0 10 EHA 26 57 35 65 / 20 0 0 10 LBL 25 57 33 65 / 20 0 0 10 HYS 28 55 37 57 / 30 0 0 10 P28 33 58 40 62 / 20 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ FN26/07 ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TOPEKA KS 254 PM CST SUN NOV 12 2006 .DISCUSSION... LATEST SURFACE ANALYSIS HAD FRONTAL BOUNDARY FROM NORTHEAST NEBRASKA SOUTHWEST INTO SOUTHWEST KANSAS TO SURFACE LOW NEAR KDHT. RADARS PICKING UP ON SOME MID LEVEL CLOUDS DEVELOPING ACROSS CENTRAL KANSAS THIS AFTERNOON. WATER VAPOR LOOP HAS BASE OF THE UPPER TROUGH OVER NEW MEXICO WITH A SHORTWAVE MOVING THROUGH THE BASE OF THE TROUGH. MID AND HIGH LEVEL MOISTURE SHOWING UP ON MOISTURE CHANNEL FROM THE BAJA OF CALIFORNIA INTO NORTHWEST MISSOURI. MODELS ARE DIFFERING ON QPF FOR TONIGHT WITH THE RUC KEEPING MOST OF THE CWA DRY BUT FOCUSING ON NORTHERN BORDER THROUGH 06Z. GFS BROADER WITH PRECIPITATION WITH HIGHEST AMOUNTS NORTH OF INTERSTATE 70. MORNING SOUNDINGS WERE VERY DRY AND FORECAST SOUNDINGS SHOW THAT IT WILL TAKE A FEW HOURS TO SATURATE THE AIRMASS FOR PRECIPITATION. LIFT WILL LAST A LITTLE LONGER OVER EASTERN KANSAS WITH UPPER TROUGH MOVING THROUGH AXIS MOVING THROUGH AROUND 09Z. HAVE EXTENDED PRECIPITATION CHANCES IN THE EASTERN COUNTIES THROUGH 09Z. CLOUDS WILL LINGER A LITTLE LONGER TONIGHT AND HAVE ADJUSTED LOWS UPWARD ACROSS THE SOUTHEAST TWO THIRDS OF THE CWA. FOR MONDAY...MOSTLY SUNNY SKIES WILL PREVAIL INTO THE EARLY AFTERNOON WITH SOME HIGH CLOUDS INCREASING IN THE AFTERNOON HOURS. ADJUSTED HIGHS SLIGHTLY FROM PREVIOUS FORECAST WITH MID 50S. MONDAY NIGHT THROUGH WEDNESDAY...MODELS STILL SHOW CONSIDERABLE DISAGREEMENT ON EVOLUTION OF H5 PATTERN AND THE AFFECTS ON THE SURFACE FEATURES. GFS IS STILL MUCH SLOWER AND DEEPER WITH DEVELOPMENT OF H5 TROUGH. WHILE OTHER MODELS HAVE TRENDED STRONGER...A WEAKER VERSION OF THE GFS IS STILL PREFERRED. AS UPPER FEATURE DIGS IN...SURFACE BOUNDARY/LOW WILL MOVE EAST ACROSS THE CENTRAL PLAINS...ACROSS THE TOP CWA TUESDAY NIGHT. NOT MUCH CHANGE MADE TO THE GOING FORECAST AS BEST CHANCES FOR PRECIP WILL BE ACROSS THE NORTHEAST CWA...IN CLOSER VICINITY TO DEEPENING SURFACE LOW. A QUICK CHANGE OVER TO SNOW LATE WEDS NIGHT/EARLY THU MORNING CANNOT BE RULED OUT...BUT STILL KEPT LIQUID PRECIP AS STILL PLENTY OF DOUBT ON COLD AIR TIMING AND MAGNITUDE. PRECIP WILL COME TO AN END BY EARLY WEDS MORNING. AS FAR AS TEMPERATURES GO...HIGHS ON TUESDAY WILL BE IN THE UPPER 50S AND LOW 60S WITH GOOD WAA. OFFSETTING THE WAA SOMEWHAT WILL BE SIGNIFICANT MID CLOUD COVER. BY COMPARISON...STRONG CAA BEHIND SURFACE LOW WILL KEEP HIGHS ON WEDS IN THE LOW TO MID 40S. THURSDAY THROUGH SUNDAY...DEEP H5 LOW LIFTS FROM THE OHIO VALLEY THROUGH THE GREAT LAKES AND INTO CANADA. FLOW ALOFT WILL INITIALLY RETURN TO ZONAL BEFORE RIDGING STARTS TO TAKE PLACE OVER THE WEEKEND ACROSS THE WESTERN HALF OF THE U.S. EXTENDED FORECAST CONTINUES TO LOOK DRY BUT TEMPERATURES LOOK SLOW TO REBOUND AS FLOW ALOFT WILL STAY FROM THE NORTHWEST THROUGH MUCH OF THE PERIOD...SO EXPECT TEMPERATURES TO BE NEAR SEASONAL AVERAGES. .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAY ME 810 PM EST SUN NOV 12 2006 .SHORT TERM /REST OF TONIGHT/... ZONE/GRID UPDATE WILL BE ISSUED TO COVER THE NORTHWARD MOVING BAND OF PRECIP...REDUCING POPS TO THE SOUTH IMMEDIATELY...AND AFTER MIDNIGHT IN THE NORTHERN ZONES. THIS BAND OF PRECIP LOOKS TO BE THE RESULT OF 700 MB DEFORMATION ZONE THAT DEVELOPED AS CLOSED LOW OVER MID-ATLANTIC RUNS INTO RIDGING TO THE NORTHEAST. PRECIP WAS ENHANCED BY LL MOISTURE CONVERGENCE ASSOCIATED WITH COASTAL FRONT. BOTH RUC/NAM SEEM TO HAVE A DECENT HANDLE ON THIS...AND INDICATE THAT DEFORMATION AND ASSOCIATED FG DO WEAKEN AS THEY MOVE NORTH...SO...EXPECTING COVERAGE AND INTENSITY OF RAIN TO DIMINISH. DID ISSUE AN FLS FOR GRAFTON/SULLIVAN IN NH THOUGH AS THIS AREA SEEMED TO SHOW SOME ENHANCEMENT FROM UPSLOPE AND RADAR ESTIMATES OF UP TO 1.5 INCHES. ONCE THE BAND LIFTS THRU...THERE SEEMS TO BE LITTLE IN THE WAY OF FORCING...AND HAVE LOWERED POPS TO CHC TO COVER A FEW SHRA...AND OCCNL DZ. -CEMPA && .AVIATION... ANY BRIEF IMPROVEMENTS TO MVFR CIGS OR VIS THIS EVE WILL BE SHORT- LIVED AS THE EASTERLY FLOW WILL QUICKLY BRING BACK THE LOW ST AND EVENTUALLY DZ THRU THE OVERNIGHT. SOME IMPROVEMENT TO MVFR CIG/VIS EXPECTED AROUND MIDDAY...AS SOME MIXING WILL DRY THINGS OUT A LITTLE BIT....BUT THE THREAT OF RA WILL REMAIN. -CEMPA && .MARINE... SCA CONTINUES TO COVER SEAS...RUNNING 3-5 FT THRU TONIGHT...AS NE FLOW PERSISTS WITH GUSTS CLOSE TO 25 KTS. -CEMPA && .PREV DISCUSSION... /ISSUED 212 PM EST SUN NOV 12 2006/ SHORT TERM /TONIGHT THROUGH MONDAY/... MOIST DAMP ONSHORE FLOW WILL CONTINUE THROUGH MONDAY...THIS MEANS OCNL RAIN DRIZZLE AND FOG. SOME CONVECTION CONTINUES TO FIRE OVER SOUTHERN NEW ENGLAND JUST NORTH OF COASTAL FRONT AXIS WHICH MAY MAKE ITS WAY NORTH INTO SOUTHERN AREAS TONIGHT AND MONDAY SO WILL FORECAST AN ISOLATED THUNDERSTORM POSSIBLE. WILL BASE TONIGHTS AND MONDAYS FORECAST ON GFS SOLUTION WHICH DEEPENS AND CLOSES OFF LOW OFF THE DELMARVA PENINSULA DURING THE DAY MONDAY AND THEN ONLY SLOWLY LIFTS IT NORTHWARD. NAM MODEL HAS BEEN THROWN OUT SINCE ITS VERY ERRATIC BEHAVIOR OF LATE. QPF AMTS TO BE LIGHT TONIGHT INTO MONDAY WITH HEAVIER AMTS EXPECTED IN THE LATER PERIODS. LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... H5 CUT OFF LOW OVER LONG ISLAND NY MON NIGHT OPENS UP AND MOVES NORTH ACROSS FORECAST AREA ON TUE. SURFACE LOW SWINGS UP INTO ST LAWRENCE VALLEY APROX SAME TIME FRAME. DECENT ONSHORE/UPSLOPE FLOW COUPLED WITH ABUNDANT MOISTURE SHOULD PROMOTE HEALTHY SOAKING TUE NIGHT...SOMEWHERE IN THE 1.5 TO 2.0 INCH RANGE THROUGH MID TO LATE DAY TUE. WED DRIES OUT SOMEWHAT...THOUGH STILL MINIMAL CHANCE SHOWERS THROUGH THU. NEXT SYSTEM PROG'D TO BRING ANOTHER SOAKING TO REGION LATER THU INTO FRI AFTERNOON WITH 24 HOUR PRECIP TOTALS IN THE 2 INCH RANGE...THEN LOOKS LIKE DRYING OUT ON TAP FOR LATER FRIDAY INTO SAT. WINDS LOOK TO BE STRONGER ON FRONT SIDE OF LATE WEEK SYSTEM. && MARINE... SHORT TERM...SCA HAS BEEN ISSUED DUE TO SLOWLY INCREASING SEAS AND WINDS TONIGHT AND MONDAY AS A VERY LONG ONSHORE FETCH CONTINUES AND LOW PRES CONTINUES TO DEVELOP OFF THE DELMARVA COAST LATER TONIGHT AND MONDAY AS HIGH PRESSURE REMAINS STACKED TO THE NORTH. LONG TERM...SCA'S ESPECIALLY FOR SEAS MON NIGHT INTO THROUGH MID WEEK WITH STRONG SCA'S FOR WIND...POSSIBLY GALE...LATER THU INTO EARLY FRI. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY FOR ANZ150 UNTIL 7 AM TUESDAY. && $$ me AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1015 PM EST SUN NOV 12 2006 .UPDATE... MAIN FCST ISSUE OVERNIGHT IS TIMING ONSET OF -SN AND SNOW ACCUMULATIONS. WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A PROGRESSIVE SHORTWAVE TROF OVER THE WRN PLAINS. AT LEADING EDGE OF TROF...00Z RAOBS SHOW 90-100KT UPPER JET EXTENDING FROM MN INTO ONTARIO. ACTUALLY...IT APPEARS THERE ARE TWO JET STREAKS. ONE IS OVER NRN ONTARIO ASSOCIATED WITH SHORTWAVE OVER NRN MANITOBA. UPPER DIVERGENCE IN RIGHT ENTRANCE OF THIS JET IS PROBABLY AIDING BAND OF PCPN DEVELOPING IN NE MN. OTHER JET IS OVER CNTRL/SW MN. RIGHT ENTRANCE DIVERGENCE WITH THIS JET IN CONJUNCTION WITH STRONGER DEEP LAYER FORCING AHEAD OF WRN PLAINS SHORTWAVE IS SUPPORTING A MORE SIGNIFICANT AREA OF PCPN FROM ERN KS/ERN NEBRASKA INTO IA. BANDED APPEARANCE OF PCPN SUGGESTS FRONTOGENESIS IS PLAYING A LARGE ROLE IN PCPN DEVELOPMENT. IN GENERAL...PCPN HAS BEEN RAPIDLY DEVELOPING/EXPANDING AND INCREASING IN INTENSITY OVER THE LAST COUPLE OF HRS. 00Z RUC SHOWS MN JET STREAK INCREASING TO 115KT AS IT TRANSLATES NNE INTO NE MN/NRN ONTARIO BY 12Z. SHARPENING ISOTACH GRADIENT AT THE SAME TIME SUGGESTS UPPER DIVERGENCE IN RIGHT ENTRANCE OF JET SHOULD STRENGTHEN. DEEP LAYER FORCING INDICATED BY 850-300MB QVECTOR CONVERGENCE ALSO STRENGTHENS WITH TIME. MEANWHILE...AT THE LOWER LEVELS...DECENT FRONTOGENESIS WILL SPREAD E INTO WRN UPPER MI. SO...SIGNAL IS CLEAR THAT PCPN THAT IS EXPANDING/INTENSIFYING TO THE W AND SW SHOULD CONTINUE TO DO SO AS IT SPREADS INTO WRN UPPER MI OVERNIGHT. INITIALLY...THERE IS DRY AIR TO OVERCOME IN THE 900-700MB LAYER PER 00Z KGRB SOUNDING (DWPT DEPRESSION AROUND 15C). EVENING TAMDAR SOUNDINGS FROM FLIGHTS OUT OF KCMX/KSAW SHOW THE DRY AIR EVEN MORE DRAMATICALLY WITH DWPT DEPRESSIONS UPWARDS OF 35C. THIS DRY AIR WILL OBVIOUSLY DELAY ONSET OF PCPN AND CUT DOWN PCPN AMOUNTS SOME. EVEN SO...STRENGTH OF FORCING AND INCREASING INTENSITY OF RADAR RETURNS UPSTREAM THIS EVENING SUGGEST SNOW MAY BRIEFLY BE MDT/HVY WHEN MAX FORCING PASSES. MOISTURE FOR SYSTEM IS NOT BAD (PRECIPITABLE WATER IS A LITTLE OVER A HALF INCH OR 150-170 PCT OF NORMAL ACROSS MN/IA)...BUT IF MORE MOISTURE WAS AVAILABLE...WOULD DEFINITELY BE CONCERNED WITH ADVY TYPE SNOW AMOUNTS. AS IT APPEARS NOW...AMOUNTS WILL BE NEARING ADVY WITH 3-4 INCH TOTAL ACCUMULATIONS QUITE LIKELY OVER THE W WHERE BEST FORCING WILL OCCUR. AMOUNTS SHOULD TRAIL OFF TO THE E SINCE STRONGEST FORCING LIFTS MORE N THAN E. ONLY VERY MINOR ADJUSTMENTS TO TIMING WILL BE MADE TO SNOW ONSET. SNOW SHOULD BEGIN FAR W AROUND 06Z AND SPREAD TO KIMT/KMQT AROUND 12Z. && .PREV DISCUSSION... ISSUED AT 405 PM EST SYNOPSIS... WV LOOP AND RUC ANALYSIS INDICATED A PROGRESSIVE PATTERN WITH A BROAD MID/UPPER LEVEL TROUGH FROM SASK AND THE NRN HIGH PLAINS TO THE CNTRL AND SRN ROCKIES. BAROCLINIC LEAF PATTERN WAS TAKING SHAPE OVER THE NRN PLAINS WITH SHRTWV ENERGY INTO WY AND 80 KT 300 MB JET STREAK TO THE NORTH INTO MANITOBA. AT THE SFC...STRONG STIFF SRLY WINDS PREVAILED BTWN A RIDGE EXTENDING FROM QUEBEC THROUGH THE CNTRL GREAT LAKES AND A TROF FROM SE MANITOBA AND NW MN INTO ERN SD/NE. RADARS INDICATED A NARROW BAND OF LIGHT SNOW OVER NE MN WITH SOME VSBYS DOWN TO 1-3SM. THE PCPN WAS SUPPORTED BY MODERATE 800-600 MB FGEN. OTHERWISE...VIS IMAGERY AND OBS SHOWED EXTENSIVE SC DECK REMAINING IN PLACE ACROSS CNTRL AND E UPR MI WHILE MID/HIGH CLOUDS STREAMED INTO W UPR MI. SHORT TERM (TONIGHT AND MONDAY)... MAIN FCST CONCERNS ARE SNOW TIMING/AMOUNTS ALONG WITH PCPN TYPE EAST. MDLS ARE IN GOOD AGREEMENT AND HAVE BEEN CONSISTENT IN BRINGING THE MID LVL TROF AXIS INTO MN BY 12Z/MON AND CNTRL UPR MI BY 00Z/TUE. MODERATE TO STRONG 700-300 QVECTOR CONV AND 800-600 FGEN WILL SUPPORT BAND OF SNOW THAT WILL MOVE ACROSS UPPER MI LATE TONIGHT AND MON. IN ADDITION...UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 300 MB JET WILL ALSO AID VERTICAL MOTION. HOWEVER...WITH THE CUTOFF LOW OFF THE E COAST AND RIDGE IN PLACE OVER THE NE CONUS AND ERN CANADA...THE MDL TREND TOWARD LIFTING THE TROUGH AND BEST QG DYNAMICS MORE TO THE ENE SEEMS REASONABLE. THIS WOULD KEEP THE GREATER SNOW POTENTIAL OVER THE WEST THIRD OF UPPER MI. SNOW/WATER RATIO IN THE 10/1-14/1 RANGE...PER COBB ALGORITHM...WITH MDLS CONSENSUS QPF IN THE 0.10-0.25 RANGE WOULD GIVE 2-3 INCH AMOUNTS IN THE WEST AND 1-2 INCH AMOUNTS CNTRL AND AN INCH OR LESS OVER THE ERN CWA. FCST SNDGS SUGGEST LOWER LEVELS WILL BE WARM ENOUGH OVER THE EAST HALF OF UPPER MI FOR MIX WITH RAIN...ESPECIALLY NEAR LAKE MI. LONG TERM (MONDAY NIGHT THROUGH NEXT SUNDAY)... MAIN FORECAST CONCERN IS PRECIPITATION CHANCES TUESDAY NIGHT THROUGH THURSDAY. MONDAY NIGHT...WHILE MONDAY\S SHRTWV IS EXITING THE EASTERN CWA EARLY IN THE EVENING...WEAK RIDGING WHICH IS CURRENTLY BUILDING INTO NORTHERN IDAHO IS PROGGED TO MOVE INTO THE WESTERN PORTIONS OF THE CWA. THEREFORE ANY LINGERING RAIN OR SNOW SHOULD END EARLY IN THE EVENING. NEXT CONCERN IS SKY COVER...SINCE WITH FRESH SNOW AND A SURFACE HIGH PRESSURE RIDGE TO COME IN...THE CLOUDS WILL REALLY IMPACT HOW COLD WE CAN GET. SUBSIDENCE COMING IN BEHIND MONDAY\S SHRTWV SHOULD HELP REMOVE MID AND HIGH CLOUDS. HOWEVER...LOW CLOUDS SEEN EXPANDING OVER EASTERN NORTH DAKOTA ON THE BACK SIDE OF THE SHRTWV\S ASSOCIATED SURFACE TROUGH MAY GET TRAPPED UNDERNEATH THE SUBSIDENCE. IN FACT...AS THE SURFACE RIDGE CROSSES DURING THE NIGHT...THE NAM AND GFS SUGGEST THE POSSIBILITY THAT THE RETURN FLOW MAY RESULT IN UPSLOPE CLOUD COVER FROM MOISTURE ADVECTED OFF LAKE MICHIGAN. THIS UPSLOPE FLOW MAY ALSO RESULT IN SOME DRIZZLE...BUT CONFIDENCE IS TOO LOW RIGHT NOW TO PUT IT IN THE FORECAST. IN ADDITION...ONCE THE WEAK UPPER LEVEL RIDGE MOVES ACROSS UPPER MICHIGAN AFTER MIDNIGHT...HIGH CLOUDS ARE EXPECTED TO COME IN. FOR NOW HAVE RAISED CLOUD COVER TO ACCOUNT FOR THESE POTENTIAL CLOUD SOURCES...AND THUS RAISED TEMPERATURES CLOSER THE 12Z VERSION OF THE MAV COOP GUIDANCE. IF MORE CLOUD COVER IS EXPECTED...LOWS WILL NEED TO BE RAISED MORE. TUESDAY...A SHRTWV LOCATED ALONG THE COAST OF OREGON...EMBEDDED WITHIN THE 130 KT JET OBSERVED THERE...IS PROGGED TO EXTEND FROM EASTERN MINNESOTA INTO MISSOURI AT 12Z. THE MODELS BEGIN TO DIVERGE WITH WHAT HAPPENS TO THIS SHRTWV AS IT RUNS INTO THE RIDGING THAT JUST MOVED ACROSS UPPER MICHIGAN...WITH THE UKMET SPLITTING IT INTO TWO (PART HEADING INTO MANITOBA AND THE OTHER INTO INDIANA)...AND THE GFS/NAM/CANADIAN INTO UPPER MICHIGAN. IN EITHER EVENT...MID LEVELS APPEAR TO BE TOO DRY FOR ANY PRECIPITATION AND THEREFORE KEEPING THE FORECAST DRY IS FINE. HOWEVER...UPSLOPE FLOW AS MENTIONED IN MONDAY NIGHT\S DISCUSSION COULD RESULT IN SOME DRIZZLE. CONFIDENCE AGAIN IS LOW. PLENTY OF CLOUD COVER...ESPECIALLY IN THE AFTERNOON...WILL HAMPER TEMPERATURES FROM GETTING TOO HIGH AND HAVE CUT TEMPERATURES JUST A FEW DEGREES. TUESDAY NIGHT AND WEDNESDAY...UPPER LOW CURRENTLY LOCATED OFF THE COAST OF BRITISH COLUMBIA IS PROGGED TO BE LOCATED OVER SOUTHERN MANITOBA AT 00Z. MODEL RUNS FROM YESTERDAY SUGGESTED THAT THIS UPPER LOW WOULD SHEAR OUT AND CROSS UPPER MICHIGAN DURING THE NIGHT INTO WEDNESDAY. HOWEVER...THIS IS NO LONGER THE CASE. THIS IS DUE TO ANOTHER SHRTWV...SLIGHTLY FARTHER OFF THE COAST OF OREGON...THAT DIGS DEEPER INTO THE PLAINS. IN FACT...THE UKMET DIGS THE SHRTWV ALL THE WAY TO TEXARKANA BY 12Z WED. OTHER MODELS ARE NOT THAT FAR SOUTH (MOSTLY INTO NE OKLAHOMA INTO MISSOURI)...BUT STILL FARTHER SOUTH THAN YESTERDAY. SINCE THE SHEARED OUT UPPER LOW IS NOT PROGGED TO AFFECT UPPER MICHIGAN DURING THIS PERIOD...HAVE REMOVED CHANCES OF PRECIPITATION. THE GFS DOES SHOW THE POSSIBILITY FOR SOME LAKE EFFECT PRECIPITATION WEDNESDAY AFTERNOON...BUT HAVE DISCOUNTED IT DUE TO THE GFS BIAS TOWARD GOING COLDER WITH TEMPERATURES AS TIME PROGRESSES AND THAT THE AFTERNOON IS TYPICALLY THE HARDEST TIME OF THE DAY FOR LAKE EFFECT. ALTHOUGH THERE IS NO PRECIPITATION PREDICTED...THERE SHOULD BE QUITE A BIT OF CLOUD COVER FROM EITHER LINGERING LOW CLOUDS FROM TUESDAY OR HIGH CLOUD ASSOCIATED WITH GENERAL SW FLOW ALOFT. THESE CLOUDS WILL PREVENT TEMPERATURES FROM DROPPING TOO MUCH TUESDAY NIGHT AND RISING TOO MUCH ON WEDNESDAY. GOING FORECAST TEMPERATURES LOOKED GOOD. WEDNESDAY NIGHT THROUGH SUNDAY...MAIN CONCERN DURING THIS PERIOD IS THE EVOLUTION OF THE UPPER TROUGH THAT IS PROGGED TO COVER MUCH OF THE MISSISSIPPI VALLEY AT THE BEGINNING OF THIS PERIOD. AT THE BASE OF THE TROUGH WILL BE THE SHRTWV DESCRIBED IN WEDNESDAY\S DISCUSSION...EITHER OVER SOUTHERN MISSISSIPPI (UKMET) OR IN CENTRAL TENNESSEE (GFS/NAM/CANADIAN 00Z ECMWF). THIS SHRTWV IS PROGGED TO LIFT NORTHEASTWARD WEDNESDAY NIGHT...RESULTING IN A DEEPENING SURFACE LOW. BY 00Z FRI...MODELS ARE IN FAIRLY GOOD AGREEMENT SUGGESTING AN UPPER 980S MB LOW NEAR THE EASTERN END OF GEORGIAN BAY. AS THIS DEEPENING PROCESSES OCCURS...COLDER AIR SHOULD DEVELOP ACROSS UPPER MICHIGAN...WHICH MAY BE ENOUGH TO GENERATE SOME LAKE ENHANCED SNOWS WEDNESDAY NIGHT. ON THURSDAY...DEFORMATION BANDING ON THE NW SIDE OF THE LOW MAY START TO IMPACT THE EASTERN U.P.. HOWEVER...ENOUGH WARM ADVECTION WRAPPING AROUND THE LOW MAY CAUSE THE PRECIPITATION TO SWITCH OVER TO RAIN...NOTED BY THE GFS RAISING 850MB TEMPS TO AROUND 0C BY 00Z FRI. THERE IS A POSSIBILITY THAT THE BAND MAY NOT AFFECT THE CWA...THOUGH...GIVEN THE TIGHT PRECIPITATION GRADIENT INDICATED BY THE GFS AND THE TIGHT 850MB DEWPOINT DEPRESSION GRADIENT ON THE 00Z ECMWF. THIS SYSTEM IS NOW PROGGED TO BE SLOWER MOVING OUT OF THE NORTHEAST U.S. THROUGH SATURDAY...WHICH ALLOWS FOR COLDER AIR TO MOVE ACROSS LAKE SUPERIOR...ENOUGH THAT LAKE EFFECT SNOW CHANCES HAVE BEEN ADDED IN. BY SUNDAY...ENOUGH WARM ADVECTION SHOULD OCCUR TO END LAKE EFFECT. HOWEVER...LATEST 12Z GFS/ECMWF SUGGEST A SLOWER DEPARTURE...CAUSED BY A SHRTWV THAT EJECTS OUT OF THE NE PACIFIC TROUGH AND CROSSES THE WESTERN GREAT LAKES ON SATURDAY. DESPITE THE ADVECTION OF SOME COLDER AIR PERIOD DURING THIS PERIOD...TEMPERATURES SHOULD REMAIN NEAR NORMAL DUE TO PERSISTENT CLOUD COVER. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ROLFSON (UPDATE) JLB (SHORT TERM) AJ (LONG TERM) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 843 PM EST SUN NOV 12 2006 .UPDATE... THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 900MB. MODEL SOLUTIONS ARE ALL TOO DRY BELOW THIS INVERSION LEVEL BASED ON THE DTX SOUNDING. IT IS NO SURPRISE THEN THAT THE STRATUS DECK HAS NOT DIMINISHED MUCH SINCE SUNSET. WITH THE FLOW NEAR THE CLOUD BASE FORECAST BY BOTH RUC AND NAM12 TO BECOME MORE SOUTHEASTERLY THROUGH 06Z...EXPECT THE STRATUS THAT IS NOW COVERING THE EASTERN THIRD OF THE FORECAST AREA TO BUILD BACK TO THE WEST. THE IR SATELLITE LOOP OVER THE LAST HOUR HAS ALREADY SHOWED THE STRATUS ADVANCING NORTHWEST ACROSS THE DETROIT METRO AREA. THE LOW LEVEL FLOW IS STILL FORECAST TO BECOME MORE SOUTH-SOUTHWESTERLY BETWEEN 09Z AND 12Z...WHICH MAY ALLOW SOME BREAKS TO DEVELOP ACROSS THE WESTERN PORTION OF THE FORECAST AREA TOWARD DAYBREAK. WILL UPDATE THE FORECAST TO REFLECT CURRENT CLOUD TRENDS. ALTHOUGH TEMPS IN LOCATIONS THAT EXPERIENCED PROLONGED CLEAR SKIES THIS EVENING HAVE DROPPED TO NEAR 30...WILL INCREASE TEMPS IN THE OVERNIGHT PERIOD TO REFLECT THE INCREASE IN CLOUD COVER. && .PREV DISCUSSION...ISSUED 624 PM EST SUN NOV 12 2006 AVIATION... A SURFACE RIDGE OF HIGH PRESSURE CURRENTLY CENTERED OVER EASTERN MICHIGAN IS FORECAST TO GRADUALLY MOVE TO THE EAST OF DETROIT BY 12Z MON. 19-22Z TAMDAR SOUNDINGS OUT OF DTW SHOW A STRONG INVERSION ABOVE 2800FT AGL. THE STRATUS DECK THAT HAS BEEN TRAPPED UNDER THIS INVERSION IS SHOWING SIGNS OF DIMINISHING...WITH A LARGE AREA OF CLEAR SKIES NOW PRESENT FROM ANN ARBOR UP TO CARO. EXPECT THIS DIMINISHING TREND WILL CONTINUE OVER THE NEXT COUPLE OF HOURS. WITH WEAK WARM AIR ADVECTION FORECAST ABOVE THE INVERSION LEVEL TONIGHT...HAVE SOME CONCERN THAT FORECAST MODEL SOUNDINGS ARE WEAKENING AND LOWERING THE INVERSION TOO MUCH TONIGHT. THE FLOW WITHIN THE CLOUD BEARING LAYER IS FORECAST TO BECOMING EAST-SOUTHEASTERLY AFTER 03Z...WHICH MAY ALLOW THE EXTENSIVE STRATUS DECK PRESENT OVER ONTARIO AND OHIO TO BUILD BACK INTO SE MICHIGAN. WILL THEREFORE KEEP SOME PERIODS OF MVFR CEILINGS IN THE TAFS INTO THE OVERNIGHT. IF THE CLEAR SKIES MANAGE TO PERSIST OVER THE TAF SITES THROUGH THE REST OF THE NIGHT...THEN REDUCED VISIBILITIES DUE TO RADIATIONAL FOG WILL BECOME A CONCERN AFTER 08Z. BETWEEN 12Z AND 15Z...THE LOW LEVEL FLOW IS FORECAST TO STRENGTHEN AND VEER MORE SOUTH-SOUTHWESTERLY. THIS ADDED MECHANICAL MIXING SHOULD HELP SCOUR OUT ANY LINGERING LOW CLOUDS OR FOG AFTER 12Z. && .PREV DISCUSSION...ISSUED 352 PM EST SUN NOV 12 2006 SHORT TERM...TONIGHT AND MONDAY NOT A WHOLE LOT TO TALK ABOUT IN THE SHORT TERM. SLOW EROSION OF STRATOCU TO CONTINUE THIS EVENING. THIS WILL SET UP A MOSTLY CLEAR NIGHT AS RIDGING HOLDS ON OVER LOWER MICHIGAN. DESPITE WARMER AIRMASS TONIGHT...GOOD RADIATIONAL COOLING CONDITIONS (CLEAR AND CALM) WILL ALLOW SURFACE TEMPERATURES TO DROP SEVERAL DEGREES LOWER THAN LAST NIGHT. LOWS IN THE UPPER 20'S WILL BE COMMONPLACE...WITH A FEW LOCATIONS DIPPING INTO THE MID 20'S. HIGH CLOUDS WILL SLIDE IN ON MONDAY IN ADVANCE OF NEXT SHORTWAVE APPROACHING FROM THE WEST. DRY AIR IN PLACE WILL BE TOO STRONG TO SUPPORT ANY PRECIP AHEAD OF THIS WAVE...AND LACK OF IDENTIFIABLE SURFACE FEATURE WILL KEEP LIFT VERY MINIMAL. PLENTY OF SUNSHINE AND WEAK RETURN FLOW SHOULD LEAD TO TEMPERATURES RIGHT AROUND NORMALS...IN THE UPPER 40S. LONG TERM...MONDAY NIGHT THROUGH SUNDAY LARGE STORM STILL SET FOR MID/LATE THIS WEEK AND ONLY HAVE TO ADJUST TIMING SLIGHTLY IN THIS FORECAST PACKAGE. MODEL CONSENSUS IS SLIGHTLY SLOWER IN LIFTING THE LEAD SURGE OF MOISTURE INTO THE AREA. INSTEAD OF WEDNESDAY MORNING...THIS MOISTURE IS NOW FORECAST TO LIFT THROUGH THE REGION ON WEDNESDAY EVENING. WILL BACK OFF ON WORDING SLIGHTLY AND FOCUS THE BEST CHANCE OF RAINFALL ON WEDNESDAY NIGHT & THURSDAY. GIVEN THE CONTINUED CONTINUITY OF THE MODELS...WILL ALSO INCREASE THE CHANCE OF PRECIPITATION TO 60% OR BETTER DURING THIS TIMEFRAME. THE TRACK/STRENGTH OF THIS SYSTEM STILL LEADS TO A LARGE INGESTION OF MILD/MOIST ATLANTIC AIR IN SOUTHEAST FLOW. THIS WILL MAKE THE MAIN EVENT MAINLY RAIN THROUGH THURSDAY...BEFORE THE COLD AIR IN THE CORE OF THE UPPER LOW LIFTS NORTH/NORTHEAST INTO THE REGION AND ALLOWS A GRADUAL TRANSITION TO RAIN/SNOW MIX AND PERHAPS ALL LIGHT SNOW BY LATE THURSDAY NIGHT OR FRIDAY...ALLOW MOST OF THE MOISTURE AND LIFT WILL BE NORTH OF THE AREA BY THEN. WILL MAINTAIN THE CURRENT TEMPERATURE FORECAST BASICALLY INTACT. GENERALLY COOL WEATHER CAN BE EXPECTED...WITH THE MILDEST PERIOD AROUND WEDNESDAY AS THIS SYSTEM APPROACHES...AND TEMPERATURES CLIMB TO NEAR 50 DURING THE DAY. THEREAFTER...A COOLING TREND CAN BE EXPECTED INTO NEXT WEEKEND...ALTHOUGH NOT TOO BAD FOR THIS TIME OF THE YEAR AS HIGHS WILL STILL CLIMB TO 40 OR BETTER. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...SHULER LONG TERM....DG AVIATION/UPDATE...CONSIDINE YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 405 PM EST SUN NOV 12 2006 .SYNOPSIS... WV LOOP AND RUC ANALYSIS INDICATED A PROGRESSIVE PATTERN WITH A BROAD MID/UPPER LEVEL TROUGH FROM SASK AND THE NRN HIGH PLAINS TO THE CNTRL AND SRN ROCKIES. BAROCLINIC LEAF PATTERN WAS TAKING SHAPE OVER THE NRN PLAINS WITH SHRTWV ENERGY INTO WY AND 80 KT 300 MB JET STREAK TO THE NORTH INTO MANITOBA. AT THE SFC...STRONG STIFF SRLY WINDS PREVAILED BTWN A RIDGE EXTENDING FROM QUEBEC THROUGH THE CNTRL GREAT LAKES AND A TROF FROM SE MANITOBA AND NW MN INTO ERN SD/NE. RADARS INDICATED A NARROW BAND OF LIGHT SNOW OVER NE MN WITH SOME VSBYS DOWN TO 1-3SM. THE PCPN WAS SUPPORTED BY MODERATE 800-600 MB FGEN. OTHERWISE...VIS IMAGERY AND OBS SHOWED EXTENSIVE SC DECK REMAINING IN PLACE ACROSS CNTRL AND E UPR MI WHILE MID/HIGH CLOUDS STREAMED INTO W UPR MI. && .SHORT TERM (TONIGHT AND MONDAY)... MAIN FCST CONCERNS ARE SNOW TIMING/AMOUNTS ALONG WITH PCPN TYPE EAST. MDLS ARE IN GOOD AGREEMENT AND HAVE BEEN CONSISTENT IN BRINGING THE MID LVL TROF AXIS INTO MN BY 12Z/MON AND CNTRL UPR MI BY 00Z/TUE. MODERATE TO STRONG 700-300 QVECTOR CONV AND 800-600 FGEN WILL SUPPORT BAND OF SNOW THAT WILL MOVE ACROSS UPPER MI LATE TONIGHT AND MON. IN ADDITION...UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 300 MB JET WILL ALSO AID VERTICAL MOTION. HOWEVER...WITH THE CUTOFF LOW OFF THE E COAST AND RIDGE IN PLACE OVER THE NE CONUS AND ERN CANADA...THE MDL TREND TOWARD LIFTING THE TROUGH AND BEST QG DYNAMICS MORE TO THE ENE SEEMS REASONABLE. THIS WOULD KEEP THE GREATER SNOW POTENTIAL OVER THE WEST THIRD OF UPPER MI. SNOW/WATER RATIO IN THE 10/1-14/1 RANGE...PER COBB ALGORITHM...WITH MDLS CONSENSUS QPF IN THE 0.10-0.25 RANGE WOULD GIVE 2-3 INCH AMOUNTS IN THE WEST AND 1-2 INCH AMOUNTS CNTRL AND AN INCH OR LESS OVER THE ERN CWA. FCST SNDGS SUGGEST LOWER LEVELS WILL BE WARM ENOUGH OVER THE EAST HALF OF UPPER MI FOR MIX WITH RAIN...ESPECIALLY NEAR LAKE MI. .LONG TERM (MONDAY NIGHT THROUGH NEXT SUNDAY)... MAIN FORECAST CONCERN IS PRECIPITATION CHANCES TUESDAY NIGHT THROUGH THURSDAY. MONDAY NIGHT...WHILE MONDAY\S SHRTWV IS EXITING THE EASTERN CWA EARLY IN THE EVENING...WEAK RIDGING WHICH IS CURRENTLY BUILDING INTO NORTHERN IDAHO IS PROGGED TO MOVE INTO THE WESTERN PORTIONS OF THE CWA. THEREFORE ANY LINGERING RAIN OR SNOW SHOULD END EARLY IN THE EVENING. NEXT CONCERN IS SKY COVER...SINCE WITH FRESH SNOW AND A SURFACE HIGH PRESSURE RIDGE TO COME IN...THE CLOUDS WILL REALLY IMPACT HOW COLD WE CAN GET. SUBSIDENCE COMING IN BEHIND MONDAY\S SHRTWV SHOULD HELP REMOVE MID AND HIGH CLOUDS. HOWEVER...LOW CLOUDS SEEN EXPANDING OVER EASTERN NORTH DAKOTA ON THE BACK SIDE OF THE SHRTWV\S ASSOCIATED SURFACE TROUGH MAY GET TRAPPED UNDERNEATH THE SUBSIDENCE. IN FACT...AS THE SURFACE RIDGE CROSSES DURING THE NIGHT...THE NAM AND GFS SUGGEST THE POSSIBILITY THAT THE RETURN FLOW MAY RESULT IN UPSLOPE CLOUD COVER FROM MOISTURE ADVECTED OFF LAKE MICHIGAN. THIS UPSLOPE FLOW MAY ALSO RESULT IN SOME DRIZZLE...BUT CONFIDENCE IS TOO LOW RIGHT NOW TO PUT IT IN THE FORECAST. IN ADDITION...ONCE THE WEAK UPPER LEVEL RIDGE MOVES ACROSS UPPER MICHIGAN AFTER MIDNIGHT...HIGH CLOUDS ARE EXPECTED TO COME IN. FOR NOW HAVE RAISED CLOUD COVER TO ACCOUNT FOR THESE POTENTIAL CLOUD SOURCES...AND THUS RAISED TEMPERATURES CLOSER THE 12Z VERSION OF THE MAV COOP GUIDANCE. IF MORE CLOUD COVER IS EXPECTED...LOWS WILL NEED TO BE RAISED MORE. TUESDAY...A SHRTWV LOCATED ALONG THE COAST OF OREGON...EMBEDDED WITHIN THE 130 KT JET OBSERVED THERE...IS PROGGED TO EXTEND FROM EASTERN MINNESOTA INTO MISSOURI AT 12Z. THE MODELS BEGIN TO DIVERGE WITH WHAT HAPPENS TO THIS SHRTWV AS IT RUNS INTO THE RIDGING THAT JUST MOVED ACROSS UPPER MICHIGAN...WITH THE UKMET SPLITTING IT INTO TWO (PART HEADING INTO MANITOBA AND THE OTHER INTO INDIANA)...AND THE GFS/NAM/CANADIAN INTO UPPER MICHIGAN. IN EITHER EVENT...MID LEVELS APPEAR TO BE TOO DRY FOR ANY PRECIPITATION AND THEREFORE KEEPING THE FORECAST DRY IS FINE. HOWEVER...UPSLOPE FLOW AS MENTIONED IN MONDAY NIGHT\S DISCUSSION COULD RESULT IN SOME DRIZZLE. CONFIDENCE AGAIN IS LOW. PLENTY OF CLOUD COVER...ESPECIALLY IN THE AFTERNOON...WILL HAMPER TEMPERATURES FROM GETTING TOO HIGH AND HAVE CUT TEMPERATURES JUST A FEW DEGREES. TUESDAY NIGHT AND WEDNESDAY...UPPER LOW CURRENTLY LOCATED OFF THE COAST OF BRITISH COLUMBIA IS PROGGED TO BE LOCATED OVER SOUTHERN MANITOBA AT 00Z. MODEL RUNS FROM YESTERDAY SUGGESTED THAT THIS UPPER LOW WOULD SHEAR OUT AND CROSS UPPER MICHIGAN DURING THE NIGHT INTO WEDNESDAY. HOWEVER...THIS IS NO LONGER THE CASE. THIS IS DUE TO ANOTHER SHRTWV...SLIGHTLY FARTHER OFF THE COAST OF OREGON...THAT DIGS DEEPER INTO THE PLAINS. IN FACT...THE UKMET DIGS THE SHRTWV ALL THE WAY TO TEXARKANA BY 12Z WED. OTHER MODELS ARE NOT THAT FAR SOUTH (MOSTLY INTO NE OKLAHOMA INTO MISSOURI)...BUT STILL FARTHER SOUTH THAN YESTERDAY. SINCE THE SHEARED OUT UPPER LOW IS NOT PROGGED TO AFFECT UPPER MICHIGAN DURING THIS PERIOD...HAVE REMOVED CHANCES OF PRECIPITATION. THE GFS DOES SHOW THE POSSIBILITY FOR SOME LAKE EFFECT PRECIPITATION WEDNESDAY AFTERNOON...BUT HAVE DISCOUNTED IT DUE TO THE GFS BIAS TOWARD GOING COLDER WITH TEMPERATURES AS TIME PROGRESSES AND THAT THE AFTERNOON IS TYPICALLY THE HARDEST TIME OF THE DAY FOR LAKE EFFECT. ALTHOUGH THERE IS NO PRECIPITATION PREDICTED...THERE SHOULD BE QUITE A BIT OF CLOUD COVER FROM EITHER LINGERING LOW CLOUDS FROM TUESDAY OR HIGH CLOUD ASSOCIATED WITH GENERAL SW FLOW ALOFT. THESE CLOUDS WILL PREVENT TEMPERATURES FROM DROPPING TOO MUCH TUESDAY NIGHT AND RISING TOO MUCH ON WEDNESDAY. GOING FORECAST TEMPERATURES LOOKED GOOD. WEDNESDAY NIGHT THROUGH SUNDAY...MAIN CONCERN DURING THIS PERIOD IS THE EVOLUTION OF THE UPPER TROUGH THAT IS PROGGED TO COVER MUCH OF THE MISSISSIPPI VALLEY AT THE BEGINNING OF THIS PERIOD. AT THE BASE OF THE TROUGH WILL BE THE SHRTWV DESCRIBED IN WEDNESDAY\S DISCUSSION...EITHER OVER SOUTHERN MISSISSIPPI (UKMET) OR IN CENTRAL TENNESSEE (GFS/NAM/CANADIAN 00Z ECMWF). THIS SHRTWV IS PROGGED TO LIFT NORTHEASTWARD WEDNESDAY NIGHT...RESULTING IN A DEEPENING SURFACE LOW. BY 00Z FRI...MODELS ARE IN FAIRLY GOOD AGREEMENT SUGGESTING AN UPPER 980S MB LOW NEAR THE EASTERN END OF GEORGIAN BAY. AS THIS DEEPENING PROCESSES OCCURS...COLDER AIR SHOULD DEVELOP ACROSS UPPER MICHIGAN...WHICH MAY BE ENOUGH TO GENERATE SOME LAKE ENHANCED SNOWS WEDNESDAY NIGHT. ON THURSDAY...DEFORMATION BANDING ON THE NW SIDE OF THE LOW MAY START TO IMPACT THE EASTERN U.P.. HOWEVER...ENOUGH WARM ADVECTION WRAPPING AROUND THE LOW MAY CAUSE THE PRECIPITATION TO SWITCH OVER TO RAIN...NOTED BY THE GFS RAISING 850MB TEMPS TO AROUND 0C BY 00Z FRI. THERE IS A POSSIBILITY THAT THE BAND MAY NOT AFFECT THE CWA...THOUGH...GIVEN THE TIGHT PRECIPITATION GRADIENT INDICATED BY THE GFS AND THE TIGHT 850MB DEWPOINT DEPRESSION GRADIENT ON THE 00Z ECMWF. THIS SYSTEM IS NOW PROGGED TO BE SLOWER MOVING OUT OF THE NORTHEAST U.S. THROUGH SATURDAY...WHICH ALLOWS FOR COLDER AIR TO MOVE ACROSS LAKE SUPERIOR...ENOUGH THAT LAKE EFFECT SNOW CHANCES HAVE BEEN ADDED IN. BY SUNDAY...ENOUGH WARM ADVECTION SHOULD OCCUR TO END LAKE EFFECT. HOWEVER...LATEST 12Z GFS/ECMWF SUGGEST A SLOWER DEPARTURE...CAUSED BY A SHRTWV THAT EJECTS OUT OF THE NE PACIFIC TROUGH AND CROSSES THE WESTERN GREAT LAKES ON SATURDAY. DESPITE THE ADVECTION OF SOME COLDER AIR PERIOD DURING THIS PERIOD...TEMPERATURES SHOULD REMAIN NEAR NORMAL DUE TO PERSISTENT CLOUD COVER. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB (SHORT TERM) AJ (LONG TERM) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1249 PM EST SUN NOV 12 2006 .AVIATION... MVFR CLOUDS TO HOLD ON A LITTLE LONGER TODAY BEFORE FINALLY SCATTERING OUT. THIN LAYER OF MOISTURE TRAPPED BENEATH SUBSIDENCE INVERSION REFUSES TO RELENT...BUT STRONG SUBSIDENCE INVERSION WILL CONTINUE TO LOWER AS LOW LEVEL WARM AIR ADVECTION PERSISTS INTO THE EVENING HOURS. THEN VFR EXPECTED TONIGHT AS CLOUDS FINALLY SCOUR OUT. CIRROSTRATUS WILL THEN MOVE IN MONDAY MORNING AHEAD OF THE NEXT SHORTWAVE. && .PREV DISCUSSION...ISSUED 1145 AM EST SUN NOV 12 2006 UPDATE... STRATOCUMULUS CLOUDS CONTINUE TO PERSIST DESPITE RIDGE AXIS OVERHEAD. SOUNDINGS REVEAL THAT THE MOISTURE TRAPPED AT 925MB IS VERY SHALLOW...AND LATEST MODEL DATA INSISTS RAPID EROSION OF THIS MOISTURE THIS AFTERNOON. BUT GIVEN LATEST SATELLITE IMAGES AND SURFACE OBSERVATIONS...WILL GO AHEAD AND SLOW DOWN THE CLEARING TREND BY A COUPLE OF HOURS. IT WILL LIKELY BE AFTER SUNSET BEFORE WE COMPLETELY SCOUR OUT THIS MOISTURE...BUT WE DO STILL EXPECT SKIES BECOMING PARTLY SUNNY DURING THE AFTERNOON...AS THE RIDGE AXIS PASSES TO THE EAST. ALSO LOWERED TEMPS ABOUT 3 DEGREES. BUT DO HOWEVER STILL EXPECT ENOUGH SUNSHINE AND WARM AIR ADVECTION TO ALLOW MIXING UP TO 925MB...WHICH WOULD LEAD TO TEMPERATURES IN THE LOW 40'S. PREV DISCUSSION...ISSUED 700 AM EST SUN NOV 12 2006 AVIATION... THE WEAK BUT PERSISTENT BANDING OF SPRINKLES/FLURRIES DETECTED COMING OFF OF SAGINAW BAY AND ALSO CLIPPING AREAS PRIMARILY NEAR THE SOUTHERN TIP OF LAKE HURON OVERNIGHT HAS OVERALL WEAKENED BUT IS STILL DISCERNIBLE IN AVAILABLE RADAR IMAGERY. HARDER TO EXPLAIN IS THE DEGREE OF CLEARING LATE IN THE OVERNIGHT OVER PARTS OF SOUTHEAST MI. BELIEVE THAT THE THINNING/CLEARING IS RELATED AT LEAST IN PART TO RELATIVE SUBSIDENCE BETWEEN THE CONVERGENCE PLUMES ASSOCIATED WITH THE LAKE EFFECT BANDS. THIS MAY ALSO EXPLAIN WHY SOME AREAS ARE TENDING TO FILL BACK IN AGAIN WITH CLOUDS AS THE LAKE EFFECT/CONVERGENCE WEAKENS. THIS WEAKENING TREND IS STILL SUPPORTED BY THE 06Z GFS/NAM AND LATEST RUC. SO...FOR THE TAFS...THE ONLY ISSUE IS IN GETTING RID OF THE LOW CLOUDS. MOST MODEL SOUNDINGS DO LOOK TO WIDEN THE LOW LEVEL TEMPERATURE/DEW POINT SPREAD ENOUGH TO SUGGEST LOSS OF THE OCCASIONAL MAINLY MVFR CEILINGS BY MID DAY...SO HAVE WRITTEN THE TAFS ACCORDINGLY. OTHERWISE...NO CEILINGS...DRY AND VFR AS RIDGE AT THE SURFACE AND ALOFT MOVES OVER THE AREA. UPDATE... RECENTLY UPDATED TO REMOVE EARLY MORNING WORDING FROM ZONES AND TO TWEAK FORECAST TODAY MAINLY FOR SKY CONDITIONS THIS MORNING. UNEXPECTED DEGREE AND PERSISTENCE OF THINNING/CLEARING OVER MUCH OF THE EASTERN AND SOUTHERN COUNTIES OF SOUTHEAST MICHIGAN. PREV DISCUSSION...ISSUED 358 AM EST SUN NOV 12 2006 SHORT TERM...TODAY AND TONIGHT MODELS IN PRETTY GOOD AGREEMENT AS FOR THE SYNOPTIC PICTURE. SURFACE RIDGE TO PASS SLOWLY EAST ACROSS SOUTHEAST MI TODAY INTO TONIGHT. AT 500 MB...MEANWHILE...SHORTWAVE RIDGE OVERHEAD TODAY TO RETREAT EAST TONIGHT. EXCEPT AS NOTED BELOW...OVERALL DESCENT SEEN IN OMEGA FIELDS TODAY INTO TONIGHT...WITH QVECTOR CONVERGENCE ALSO INDICATING MOSTLY DIVERGENCE/SUBSIDENCE. 850 TO 500 MB MOISTURE RATHER MEAGER THROUGH TONIGHT. INCREASING CIRRUS...THOUGH...LIKELY TO BE SEEN MAINLY LATE TONIGHT BEHIND RIDGE ALOFT. LOW LEVEL MOISTURE...AS AT 925 MB...EXPECTED TO DIMINISH TODAY. THE EXCEPTION TO NO WEATHER IS THE OVERNIGHT SPRINKLES AND FLURRIES SEEN OVER MUCH OF THE FORECAST AREA...LARGELY RELATED TO LAKE EFFECT FROM NORTH TO NORTHEAST FLOW OFF OF LAKE HURON. DELTA TS INTO THE LOWER TEENS EARLIER IN THE NIGHT SHOULD LESSEN STEADILY THIS MORNING AS 850 MB TEMPERATURES WARM BEHIND THE BRIEF THERMAL TROUGH. NAM/RUC AND GFS SHOW GOOD LOW LEVEL CONVERGENCE...TENDING TO MAXIMIZE AROUND 06Z...ALSO ON THE WANE THIS MORNING. NAM ALSO SHOWS MODEST 950 MB OMEGA LIFT...MAINLY IN THE THUMB...WANING THIS MORNING. WILL CARRY MENTION OF SPRINKLES OR FLURRIES INTO THE MORNING FOR MOST OF THE AREA...THEN RIDGE OVERHEAD THIS AFTERNOON SHOULD KILL OFF ANY MORE POSSIBILITY OF THIS TRACE PRECIPITATION. PERSISTENCE OF SPRINKLES...AS OPPOSED TO FLURRIES...SEEMS RELATED TO SHALLOW DEPTH OF MOISTURE AND THUS VERY POOR ICE NUCLEATION POTENTIAL...AS PER MODEL SOUNDINGS. AS FOR CLOUD COVER TODAY...MOST MODELS INDICATE LESSENING BY AFTERNOON...AND WILL SO INDICATE. SATELLITE IMAGERY ALREADY SHOWING SOME THIN SPOTS/HOLES IN THE CLOUD COVER. DAYTIME MIXING SHOULD AID IN CLOUD COVER DECREASE. LONG TERM...MONDAY THROUGH SUNDAY CONFIDENCE IS INCREASING FOR A POTENT STORM TO IMPACT THE REGION FOR MID WEEK...HOWEVER...PREDICTABILITY OF THE EVENTUAL UPPER FLOW REGIME ACROSS THE CONUS REMAINS BELOW AVERAGE. SATELLITE DERIVED WINDS IN THE EASTERN PACIFIC AS OF 03Z WERE AVERAGING AROUND 120KTS WITH A DEVELOPING JET STREAK APPROACHING 150KTS EAST OF 150W IN BETWEEN 40-50N. GLOBAL MODELS SEEM TO HAVE INITIALIZED THE PACIFIC JET ORIENTATION AND GENERAL STRENGTH AS THE ECMWF APPEARS TO HAVE PICKED UP THE JET STREAK EARLIER THAN THE OTHER OPERATIONAL GLOBAL MODELS. THIS FEATURE(S) WILL BE OUR FORECAST CHALLENGE FOR THIS UPCOMING WEEK. BEGINNING WITH MONDAY...LONG WAVE TROUGH CURRENTLY PROGRESSING THROUGH THE INTERMOUNTAIN WEST AND EMBEDDED SHORT WAVE ACROSS THE FOUR CORNERS WILL LIFT NORTHEAST THROUGH THE DAY AS SHORT WAVE RIDGE AND SURFACE HIGH PRECEDING IT SLIDES FURTHER EAST. WHILE A GOOD AERIAL COVERAGE OF PRECIP IS EXPECTED TO ACCOMPANY THIS FEATURE INITIALLY...DECREASING THERMAL GRADIENT IN THE LOW-MID LEVELS ACROSS THE MID-UPPER MISSISSIPPI RIVER VALLEY AND BEST UPPER SUPPORT WILL LIFT INTO CANADA AND REDUCE THE CHANCES OF PRECIP FOR THE CWA. IN FACT...HARD TO FIND A MODEL THAT PRINTS ANY QPF ACROSS THE CWA. DO NOT FEEL COMPELLED TO REMOVE POPS COMPLETELY AND WILL RETAIN THE CURRENT FORECAST WITH 20% POPS ALONG AND NORTH OF 8-MILE WITH 30% POPS AROUND THE TRI CITIES. THEN A BRIEF RESPITE MONDAY NIGHT INTO TUESDAY AS WEAK SURFACE HIGH AND SHORT WAVE RIDGE AXIS MOVES ACROSS THE GREAT LAKES. HOWEVER... LOW LEVEL MOISTURE REMAINS RATHER HIGH AS OBSERVED IN THE GFS/NAM/WRF-HEMI SOUNDINGS HENCE THE PERCENT CLOUD COVER WILL REMAIN RATHER HIGH THROUGH EARLY TUESDAY MORNING. POTENT PACIFIC JET COMES ASHORE AND DIVES SOUTHEAST INTO THE THE FOUR CORNERS REGION TUESDAY NIGHT WITH SURFACE LOW DEVELOPING IN THE VICINITY OF THE PANHANDLE OF TEXAS. DEPENDING ON HOW THIS PATTERN UNFOLDS ACROSS THE CONUS...TRENDS IN THE GLOBAL MODELS SUGGEST UPPER PATTERN QUICKLY BECOMES NEGATIVELY TILTED AS GULF OF MEXICO MOISTURE ADVANCES NORTHWARD WEDNESDAY-WEDNESDAY NIGHT. CROSS SECTIONS FROM THE GFS SHOW A RATHER POTENT PETTERSSEN 2-D FGEN LAYER BETWEEN 850-700MB WITH AN INCREASED SLANTWISE INSTABILITY (INCLUDING DEPTH) JUST ABOVE THIS LAYER AS SUGGESTED IN THE LOWERING EPV/S ACROSS THE CWA. COULD SEE A BAND(S) OF HEAVY RAIN AND THUNDER WEDNESDAY AFTERNOON INTO THURSDAY MORNING...THIS WILL NEED TO MONITORED CLOSELY AS PWATS ARE EXPECTED TO CLIMB IN EXCESS OF 1 INCH. LOW BECOMES VERTICALLY STACKED ACROSS THE STATE THROUGH THURSDAY WITH A SLOW RETREAT NORTHWARD THROUGH THE END OF THIS WEEK. 850MB TEMPS DROP BACK TOWARD THE NEGATIVE TERRITORY AND PERHAPS EVEN LOWER INTO THE WEEKEND AS UPPER FLOW AMPLIFIES TOWARD A RIDGE ACROSS THE ROCKIES AND A TROUGH ACROSS THE GREAT LAKES/MIDDLE ATLANTIC COAST. THIS SETS THE STAGE FOR THE CHANCE OF SNOW SHOWERS FROM THE COLD/MOIST CYCLONIC FLOW AND CONTRIBUTIONS FROM LAKE MICHIGAN. WILL GO LOWER THAN MEX NUMBERS AND ADD POPS FOR SNOW THROUGH AT LEAST NEXT SATURDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...LHZ421...NEARSHORE WATERS FROM PORT AUSTIN T SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION/UPDATE...JDS SHORT TERM...DWD LONG TERM....BGM YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1145 AM EST SUN NOV 12 2006 .UPDATE... STRATOCUMULUS CLOUDS CONTINUE TO PERSIST DESPITE RIDGE AXIS OVERHEAD. SOUNDINGS REVEAL THAT THE MOISTURE TRAPPED AT 925MB IS VERY SHALLOW...AND LATEST MODEL DATA INSISTS RAPID EROSION OF THIS MOISTURE THIS AFTERNOON. BUT GIVEN LATEST SATELLITE IMAGES AND SURFACE OBSERVATIONS...WILL GO AHEAD AND SLOW DOWN THE CLEARING TREND BY A COUPLE OF HOURS. IT WILL LIKELY BE AFTER SUNSET BEFORE WE COMPLETELY SCOUR OUT THIS MOISTURE...BUT WE DO STILL EXPECT SKIES BECOMING PARTLY SUNNY DURING THE AFTERNOON...AS THE RIDGE AXIS PASSES TO THE EAST. ALSO LOWERED TEMPS ABOUT 3 DEGREES. BUT DO HOWEVER STILL EXPECT ENOUGH SUNSHINE AND WARM AIR ADVECTION TO ALLOW MIXING UP TO 925MB...WHICH WOULD LEAD TO TEMPERATURES IN THE LOW 40'S. && .PREV DISCUSSION...ISSUED 700 AM EST SUN NOV 12 2006 AVIATION... THE WEAK BUT PERSISTENT BANDING OF SPRINKLES/FLURRIES DETECTED COMING OFF OF SAGINAW BAY AND ALSO CLIPPING AREAS PRIMARILY NEAR THE SOUTHERN TIP OF LAKE HURON OVERNIGHT HAS OVERALL WEAKENED BUT IS STILL DISCERNIBLE IN AVAILABLE RADAR IMAGERY. HARDER TO EXPLAIN IS THE DEGREE OF CLEARING LATE IN THE OVERNIGHT OVER PARTS OF SOUTHEAST MI. BELIEVE THAT THE THINNING/CLEARING IS RELATED AT LEAST IN PART TO RELATIVE SUBSIDENCE BETWEEN THE CONVERGENCE PLUMES ASSOCIATED WITH THE LAKE EFFECT BANDS. THIS MAY ALSO EXPLAIN WHY SOME AREAS ARE TENDING TO FILL BACK IN AGAIN WITH CLOUDS AS THE LAKE EFFECT/CONVERGENCE WEAKENS. THIS WEAKENING TREND IS STILL SUPPORTED BY THE 06Z GFS/NAM AND LATEST RUC. SO...FOR THE TAFS...THE ONLY ISSUE IS IN GETTING RID OF THE LOW CLOUDS. MOST MODEL SOUNDINGS DO LOOK TO WIDEN THE LOW LEVEL TEMPERATURE/DEW POINT SPREAD ENOUGH TO SUGGEST LOSS OF THE OCCASIONAL MAINLY MVFR CEILINGS BY MID DAY...SO HAVE WRITTEN THE TAFS ACCORDINGLY. OTHERWISE...NO CEILINGS...DRY AND VFR AS RIDGE AT THE SURFACE AND ALOFT MOVES OVER THE AREA. UPDATE... RECENTLY UPDATED TO REMOVE EARLY MORNING WORDING FROM ZONES AND TO TWEAK FORECAST TODAY MAINLY FOR SKY CONDITIONS THIS MORNING. UNEXPECTED DEGREE AND PERSISTENCE OF THINNING/CLEARING OVER MUCH OF THE EASTERN AND SOUTHERN COUNTIES OF SOUTHEAST MICHIGAN. PREV DISCUSSION...ISSUED 358 AM EST SUN NOV 12 2006 SHORT TERM...TODAY AND TONIGHT MODELS IN PRETTY GOOD AGREEMENT AS FOR THE SYNOPTIC PICTURE. SURFACE RIDGE TO PASS SLOWLY EAST ACROSS SOUTHEAST MI TODAY INTO TONIGHT. AT 500 MB...MEANWHILE...SHORTWAVE RIDGE OVERHEAD TODAY TO RETREAT EAST TONIGHT. EXCEPT AS NOTED BELOW...OVERALL DESCENT SEEN IN OMEGA FIELDS TODAY INTO TONIGHT...WITH QVECTOR CONVERGENCE ALSO INDICATING MOSTLY DIVERGENCE/SUBSIDENCE. 850 TO 500 MB MOISTURE RATHER MEAGER THROUGH TONIGHT. INCREASING CIRRUS...THOUGH...LIKELY TO BE SEEN MAINLY LATE TONIGHT BEHIND RIDGE ALOFT. LOW LEVEL MOISTURE...AS AT 925 MB...EXPECTED TO DIMINISH TODAY. THE EXCEPTION TO NO WEATHER IS THE OVERNIGHT SPRINKLES AND FLURRIES SEEN OVER MUCH OF THE FORECAST AREA...LARGELY RELATED TO LAKE EFFECT FROM NORTH TO NORTHEAST FLOW OFF OF LAKE HURON. DELTA TS INTO THE LOWER TEENS EARLIER IN THE NIGHT SHOULD LESSEN STEADILY THIS MORNING AS 850 MB TEMPERATURES WARM BEHIND THE BRIEF THERMAL TROUGH. NAM/RUC AND GFS SHOW GOOD LOW LEVEL CONVERGENCE...TENDING TO MAXIMIZE AROUND 06Z...ALSO ON THE WANE THIS MORNING. NAM ALSO SHOWS MODEST 950 MB OMEGA LIFT...MAINLY IN THE THUMB...WANING THIS MORNING. WILL CARRY MENTION OF SPRINKLES OR FLURRIES INTO THE MORNING FOR MOST OF THE AREA...THEN RIDGE OVERHEAD THIS AFTERNOON SHOULD KILL OFF ANY MORE POSSIBILITY OF THIS TRACE PRECIPITATION. PERSISTENCE OF SPRINKLES...AS OPPOSED TO FLURRIES...SEEMS RELATED TO SHALLOW DEPTH OF MOISTURE AND THUS VERY POOR ICE NUCLEATION POTENTIAL...AS PER MODEL SOUNDINGS. AS FOR CLOUD COVER TODAY...MOST MODELS INDICATE LESSENING BY AFTERNOON...AND WILL SO INDICATE. SATELLITE IMAGERY ALREADY SHOWING SOME THIN SPOTS/HOLES IN THE CLOUD COVER. DAYTIME MIXING SHOULD AID IN CLOUD COVER DECREASE. LONG TERM...MONDAY THROUGH SUNDAY CONFIDENCE IS INCREASING FOR A POTENT STORM TO IMPACT THE REGION FOR MID WEEK...HOWEVER...PREDICTABILITY OF THE EVENTUAL UPPER FLOW REGIME ACROSS THE CONUS REMAINS BELOW AVERAGE. SATELLITE DERIVED WINDS IN THE EASTERN PACIFIC AS OF 03Z WERE AVERAGING AROUND 120KTS WITH A DEVELOPING JET STREAK APPROACHING 150KTS EAST OF 150W IN BETWEEN 40-50N. GLOBAL MODELS SEEM TO HAVE INITIALIZED THE PACIFIC JET ORIENTATION AND GENERAL STRENGTH AS THE ECMWF APPEARS TO HAVE PICKED UP THE JET STREAK EARLIER THAN THE OTHER OPERATIONAL GLOBAL MODELS. THIS FEATURE(S) WILL BE OUR FORECAST CHALLENGE FOR THIS UPCOMING WEEK. BEGINNING WITH MONDAY...LONG WAVE TROUGH CURRENTLY PROGRESSING THROUGH THE INTERMOUNTAIN WEST AND EMBEDDED SHORT WAVE ACROSS THE FOUR CORNERS WILL LIFT NORTHEAST THROUGH THE DAY AS SHORT WAVE RIDGE AND SURFACE HIGH PRECEDING IT SLIDES FURTHER EAST. WHILE A GOOD AERIAL COVERAGE OF PRECIP IS EXPECTED TO ACCOMPANY THIS FEATURE INITIALLY...DECREASING THERMAL GRADIENT IN THE LOW-MID LEVELS ACROSS THE MID-UPPER MISSISSIPPI RIVER VALLEY AND BEST UPPER SUPPORT WILL LIFT INTO CANADA AND REDUCE THE CHANCES OF PRECIP FOR THE CWA. IN FACT...HARD TO FIND A MODEL THAT PRINTS ANY QPF ACROSS THE CWA. DO NOT FEEL COMPELLED TO REMOVE POPS COMPLETELY AND WILL RETAIN THE CURRENT FORECAST WITH 20% POPS ALONG AND NORTH OF 8-MILE WITH 30% POPS AROUND THE TRI CITIES. THEN A BRIEF RESPITE MONDAY NIGHT INTO TUESDAY AS WEAK SURFACE HIGH AND SHORT WAVE RIDGE AXIS MOVES ACROSS THE GREAT LAKES. HOWEVER... LOW LEVEL MOISTURE REMAINS RATHER HIGH AS OBSERVED IN THE GFS/NAM/WRF-HEMI SOUNDINGS HENCE THE PERCENT CLOUD COVER WILL REMAIN RATHER HIGH THROUGH EARLY TUESDAY MORNING. POTENT PACIFIC JET COMES ASHORE AND DIVES SOUTHEAST INTO THE THE FOUR CORNERS REGION TUESDAY NIGHT WITH SURFACE LOW DEVELOPING IN THE VICINITY OF THE PANHANDLE OF TEXAS. DEPENDING ON HOW THIS PATTERN UNFOLDS ACROSS THE CONUS...TRENDS IN THE GLOBAL MODELS SUGGEST UPPER PATTERN QUICKLY BECOMES NEGATIVELY TILTED AS GULF OF MEXICO MOISTURE ADVANCES NORTHWARD WEDNESDAY-WEDNESDAY NIGHT. CROSS SECTIONS FROM THE GFS SHOW A RATHER POTENT PETTERSSEN 2-D FGEN LAYER BETWEEN 850-700MB WITH AN INCREASED SLANTWISE INSTABILITY (INCLUDING DEPTH) JUST ABOVE THIS LAYER AS SUGGESTED IN THE LOWERING EPV/S ACROSS THE CWA. COULD SEE A BAND(S) OF HEAVY RAIN AND THUNDER WEDNESDAY AFTERNOON INTO THURSDAY MORNING...THIS WILL NEED TO MONITORED CLOSELY AS PWATS ARE EXPECTED TO CLIMB IN EXCESS OF 1 INCH. LOW BECOMES VERTICALLY STACKED ACROSS THE STATE THROUGH THURSDAY WITH A SLOW RETREAT NORTHWARD THROUGH THE END OF THIS WEEK. 850MB TEMPS DROP BACK TOWARD THE NEGATIVE TERRITORY AND PERHAPS EVEN LOWER INTO THE WEEKEND AS UPPER FLOW AMPLIFIES TOWARD A RIDGE ACROSS THE ROCKIES AND A TROUGH ACROSS THE GREAT LAKES/MIDDLE ATLANTIC COAST. THIS SETS THE STAGE FOR THE CHANCE OF SNOW SHOWERS FROM THE COLD/MOIST CYCLONIC FLOW AND CONTRIBUTIONS FROM LAKE MICHIGAN. WILL GO LOWER THAN MEX NUMBERS AND ADD POPS FOR SNOW THROUGH AT LEAST NEXT SATURDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...LHZ421...NEARSHORE WATERS FROM PORT AUSTIN T SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ UPDATE...JDS SHORT TERM...DWD LONG TERM....BGM YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 700 AM EST SUN NOV 12 2006 .AVIATION... THE WEAK BUT PERSISTENT BANDING OF SPRINKLES/FLURRIES DETECTED COMING OFF OF SAGINAW BAY AND ALSO CLIPPING AREAS PRIMARILY NEAR THE SOUTHERN TIP OF LAKE HURON OVERNIGHT HAS OVERALL WEAKENED BUT IS STILL DISCERNIBLE IN AVAILABLE RADAR IMAGERY. HARDER TO EXPLAIN IS THE DEGREE OF CLEARING LATE IN THE OVERNIGHT OVER PARTS OF SOUTHEAST MI. BELIEVE THAT THE THINNING/CLEARING IS RELATED AT LEAST IN PART TO RELATIVE SUBSIDENCE BETWEEN THE CONVERGENCE PLUMES ASSOCIATED WITH THE LAKE EFFECT BANDS. THIS MAY ALSO EXPLAIN WHY SOME AREAS ARE TENDING TO FILL BACK IN AGAIN WITH CLOUDS AS THE LAKE EFFECT/CONVERGENCE WEAKENS. THIS WEAKENING TREND IS STILL SUPPORTED BY THE 06Z GFS/NAM AND LATEST RUC. SO...FOR THE TAFS...THE ONLY ISSUE IS IN GETTING RID OF THE LOW CLOUDS. MOST MODEL SOUNDINGS DO LOOK TO WIDEN THE LOW LEVEL TEMPERATURE/DEW POINT SPREAD ENOUGH TO SUGGEST LOSS OF THE OCCASIONAL MAINLY MVFR CEILINGS BY MID DAY...SO HAVE WRITTEN THE TAFS ACCORDINGLY. OTHERWISE...NO CEILINGS...DRY AND VFR AS RIDGE AT THE SURFACE AND ALOFT MOVES OVER THE AREA. && .UPDATE... RECENTLY UPDATED TO REMOVE EARLY MORNING WORDING FROM ZONES AND TO TWEAK FORECAST TODAY MAINLY FOR SKY CONDITIONS THIS MORNING. UNEXPECTED DEGREE AND PERSISTENCE OF THINNING/CLEARING OVER MUCH OF THE EASTERN AND SOUTHERN COUNTIES OF SOUTHEAST MICHIGAN. && .PREV DISCUSSION...ISSUED 358 AM EST SUN NOV 12 2006 SHORT TERM...TODAY AND TONIGHT MODELS IN PRETTY GOOD AGREEMENT AS FOR THE SYNOPTIC PICTURE. SURFACE RIDGE TO PASS SLOWLY EAST ACROSS SOUTHEAST MI TODAY INTO TONIGHT. AT 500 MB...MEANWHILE...SHORTWAVE RIDGE OVERHEAD TODAY TO RETREAT EAST TONIGHT. EXCEPT AS NOTED BELOW...OVERALL DESCENT SEEN IN OMEGA FIELDS TODAY INTO TONIGHT...WITH QVECTOR CONVERGENCE ALSO INDICATING MOSTLY DIVERGENCE/SUBSIDENCE. 850 TO 500 MB MOISTURE RATHER MEAGER THROUGH TONIGHT. INCREASING CIRRUS...THOUGH...LIKELY TO BE SEEN MAINLY LATE TONIGHT BEHIND RIDGE ALOFT. LOW LEVEL MOISTURE...AS AT 925 MB...EXPECTED TO DIMINISH TODAY. THE EXCEPTION TO NO WEATHER IS THE OVERNIGHT SPRINKLES AND FLURRIES SEEN OVER MUCH OF THE FORECAST AREA...LARGELY RELATED TO LAKE EFFECT FROM NORTH TO NORTHEAST FLOW OFF OF LAKE HURON. DELTA TS INTO THE LOWER TEENS EARLIER IN THE NIGHT SHOULD LESSEN STEADILY THIS MORNING AS 850 MB TEMPERATURES WARM BEHIND THE BRIEF THERMAL TROUGH. NAM/RUC AND GFS SHOW GOOD LOW LEVEL CONVERGENCE...TENDING TO MAXIMIZE AROUND 06Z...ALSO ON THE WANE THIS MORNING. NAM ALSO SHOWS MODEST 950 MB OMEGA LIFT...MAINLY IN THE THUMB...WANING THIS MORNING. WILL CARRY MENTION OF SPRINKLES OR FLURRIES INTO THE MORNING FOR MOST OF THE AREA...THEN RIDGE OVERHEAD THIS AFTERNOON SHOULD KILL OFF ANY MORE POSSIBILITY OF THIS TRACE PRECIPITATION. PERSISTENCE OF SPRINKLES...AS OPPOSED TO FLURRIES...SEEMS RELATED TO SHALLOW DEPTH OF MOISTURE AND THUS VERY POOR ICE NUCLEATION POTENTIAL...AS PER MODEL SOUNDINGS. AS FOR CLOUD COVER TODAY...MOST MODELS INDICATE LESSENING BY AFTERNOON...AND WILL SO INDICATE. SATELLITE IMAGERY ALREADY SHOWING SOME THIN SPOTS/HOLES IN THE CLOUD COVER. DAYTIME MIXING SHOULD AID IN CLOUD COVER DECREASE. LONG TERM...MONDAY THROUGH SUNDAY CONFIDENCE IS INCREASING FOR A POTENT STORM TO IMPACT THE REGION FOR MID WEEK...HOWEVER...PREDICTABILITY OF THE EVENTUAL UPPER FLOW REGIME ACROSS THE CONUS REMAINS BELOW AVERAGE. SATELLITE DERIVED WINDS IN THE EASTERN PACIFIC AS OF 03Z WERE AVERAGING AROUND 120KTS WITH A DEVELOPING JET STREAK APPROACHING 150KTS EAST OF 150W IN BETWEEN 40-50N. GLOBAL MODELS SEEM TO HAVE INITIALIZED THE PACIFIC JET ORIENTATION AND GENERAL STRENGTH AS THE ECMWF APPEARS TO HAVE PICKED UP THE JET STREAK EARLIER THAN THE OTHER OPERATIONAL GLOBAL MODELS. THIS FEATURE(S) WILL BE OUR FORECAST CHALLENGE FOR THIS UPCOMING WEEK. BEGINNING WITH MONDAY...LONG WAVE TROUGH CURRENTLY PROGRESSING THROUGH THE INTERMOUNTAIN WEST AND EMBEDDED SHORT WAVE ACROSS THE FOUR CORNERS WILL LIFT NORTHEAST THROUGH THE DAY AS SHORT WAVE RIDGE AND SURFACE HIGH PRECEDING IT SLIDES FURTHER EAST. WHILE A GOOD AERIAL COVERAGE OF PRECIP IS EXPECTED TO ACCOMPANY THIS FEATURE INITIALLY...DECREASING THERMAL GRADIENT IN THE LOW-MID LEVELS ACROSS THE MID-UPPER MISSISSIPPI RIVER VALLEY AND BEST UPPER SUPPORT WILL LIFT INTO CANADA AND REDUCE THE CHANCES OF PRECIP FOR THE CWA. IN FACT...HARD TO FIND A MODEL THAT PRINTS ANY QPF ACROSS THE CWA. DO NOT FEEL COMPELLED TO REMOVE POPS COMPLETELY AND WILL RETAIN THE CURRENT FORECAST WITH 20% POPS ALONG AND NORTH OF 8-MILE WITH 30% POPS AROUND THE TRI CITIES. THEN A BRIEF RESPITE MONDAY NIGHT INTO TUESDAY AS WEAK SURFACE HIGH AND SHORT WAVE RIDGE AXIS MOVES ACROSS THE GREAT LAKES. HOWEVER... LOW LEVEL MOISTURE REMAINS RATHER HIGH AS OBSERVED IN THE GFS/NAM/WRF-HEMI SOUNDINGS HENCE THE PERCENT CLOUD COVER WILL REMAIN RATHER HIGH THROUGH EARLY TUESDAY MORNING. POTENT PACIFIC JET COMES ASHORE AND DIVES SOUTHEAST INTO THE THE FOUR CORNERS REGION TUESDAY NIGHT WITH SURFACE LOW DEVELOPING IN THE VICINITY OF THE PANHANDLE OF TEXAS. DEPENDING ON HOW THIS PATTERN UNFOLDS ACROSS THE CONUS...TRENDS IN THE GLOBAL MODELS SUGGEST UPPER PATTERN QUICKLY BECOMES NEGATIVELY TILTED AS GULF OF MEXICO MOISTURE ADVANCES NORTHWARD WEDNESDAY-WEDNESDAY NIGHT. CROSS SECTIONS FROM THE GFS SHOW A RATHER POTENT PETTERSSEN 2-D FGEN LAYER BETWEEN 850-700MB WITH AN INCREASED SLANTWISE INSTABILITY (INCLUDING DEPTH) JUST ABOVE THIS LAYER AS SUGGESTED IN THE LOWERING EPV/S ACROSS THE CWA. COULD SEE A BAND(S) OF HEAVY RAIN AND THUNDER WEDNESDAY AFTERNOON INTO THURSDAY MORNING...THIS WILL NEED TO MONITORED CLOSELY AS PWATS ARE EXPECTED TO CLIMB IN EXCESS OF 1 INCH. LOW BECOMES VERTICALLY STACKED ACROSS THE STATE THROUGH THURSDAY WITH A SLOW RETREAT NORTHWARD THROUGH THE END OF THIS WEEK. 850MB TEMPS DROP BACK TOWARD THE NEGATIVE TERRITORY AND PERHAPS EVEN LOWER INTO THE WEEKEND AS UPPER FLOW AMPLIFIES TOWARD A RIDGE ACROSS THE ROCKIES AND A TROUGH ACROSS THE GREAT LAKES/MIDDLE ATLANTIC COAST. THIS SETS THE STAGE FOR THE CHANCE OF SNOW SHOWERS FROM THE COLD/MOIST CYCLONIC FLOW AND CONTRIBUTIONS FROM LAKE MICHIGAN. WILL GO LOWER THAN MEX NUMBERS AND ADD POPS FOR SNOW THROUGH AT LEAST NEXT SATURDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...LHZ421... NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON... UNTIL 5 PM SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION AND UPDATE...DWD SHORT TERM...DWD LONG TERM....BGM YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 936 PM CST SUN NOV 12 2006 .UPDATE... STILL A BIT TRICKY SITUATION OVERNIGHT. LAPS 1000-850 THICKNESS OF 1305 METERS DIPS DOWN NEAR THE TWIN CITIES AND BACK NW TOWARD KAXN. THIS GENERALLY IN AREA WHERE SNOW HAS BEEN REPORTED. 00Z RUC AND NAM SHOWING FAVORABLE THICKNESSES FOR SNOW DROPPING A LITTLE FARTHER SOUTH OVERNIGHT AND THEN THE COLUMN COOLING IN WI OVERNIGHT. KMPX SOUNDING DID SHOW SOME EVAPORATIVE COOLING POTENTIAL..WHICH DID WORK OUT. LOTS OF TEMPS IN MID 30S...AND EVEN UPPER 30S IN WI...SO THERE WILL BE SOME MELTING INITIALLY. AS FAR AS FORCING GOES..THERE IS A FRONTOGENETIC SIGNATURE OVER EAST CENTRAL AND SOUTH CENTRAL MN..WHICH IS FORECAST TO GRADUALLY SHIFT INTO WI OVERNIGHT. THETA E ADVECTION IN THE 850-700 MB LAYER IS CURRENTLY ON THE EDGE OF FRONTOGENESIS AREA. THE THETA E ADVECTION WEAKENS OR MOVES OFF FARTHER EAST OF OUR WI AREA LATE TONIGHT. WITH THE INITIALLY WARM TEMPS...AND GRADUALLY WEAKENING FORCING.. FEEL THAT THE AROUND 3 INCHES WILL BE OK IN WI..AND AROUND 2 IN EASTERN INTO SOUTH CENTRAL MN. && .PREV DISCUSSION... /ISSUED 244 PM CST SUN NOV 12 2006/ DISCUSSION... CONCERNS DURING THE FORECAST PERIOD THROUGH NEXT SUNDAY REVOLVE AROUND A SNOW EVENT OVER THE EASTERN CWA TONIGHT AND THE THREAT OF MORE SNOW TUESDAY NIGHT AND WEDNESDAY. GOOD CONTINUITY CONTINUES WITH THE SYSTEM TONIGHT BETWEEN THE NAM AND GFS. THE RIGHT ENTRANCE REGION OF THE JET STRENGTHENS TO OUR NORTH OVERNIGHT WITH INCREASING MID LEVEL FRONTOGENESIS. THE FWF BLOSSOMS OVER EAST CENTRAL MN AND WEST CENTRAL WI BETWEEN 06Z AND 12Z. CROSS SECTION SHOWS BOTH DEEP MOISTURE AND AGEOSTROPHIC VERTICAL CIRCULATION PEAKING IN THE 09Z TO 12Z TIME FRAME OVER WEST CENTRAL WI. OMEGA IS ALSO MAXIMIZED AT AND JUST BELOW THE PREFERRED TEMPERATURES FOR ICE CRYSTALS FORMATION. LAYER EPV IS A LITTLE MORE POSITIVE THAN WHAT IS PREFERRED BUT A SMALL AREA OF .25 OR LESS DOES EXIST. 295K THETA SURFACE INDICATES MIXING RATIOS OF 3 G/KG. NAM/GFS BUFKIT COBB TECHNIQUE INDICATES 3 INCHES OF SNOW ACCUMULATION AT BOTH EAU AND HYR WITH SNOW AMOUNTS DIMINISHING BACK TO AN INCH OR SO IN THE TWIN CITIES. WILL CONTINUE WITH A 2 TO 3 INCH FORECAST FOR WEST CENTRAL WI BUT A LITTLE CONCERNED GIVEN THE FORCING THAT THE LADYSMITH TO EAU CLAIRE AREA COULD BE HIGHER. 12Z NCEP NMM WRF SHOWS AT LEAST .25 LIQUID ACCUMULATION BY 12Z MONDAY IN THE AFOREMENTIONED AREA WHILE THE NCEP ARW WRF SHOWS THE .25 AREA JUST EAST OF THE FA. COLLABORATION WITH NEIGHBORS TO THE NORTH AND SOUTHEAST WAS TO STAY BELOW ADVISORY CRITERIA DUE TO THE SPEED OF THE SYSTEM. DRY CONDITIONS MONDAY AND MONDAY NIGHT. FEW CHANGES MADE TO THE TUESDAY THROUGH WEDNESDAY FORECAST AS A SHORT WAVE DEEPENS EAST OF THE ROCKIES. SINGLE RUN GFS SOLUTION IS STILL BANKING ON A BIG STORM JUST SOUTH OF HERE ON WEDNESDAY. 12Z ECMWF NOT AS DEEP...FURTHER SOUTHEAST...ALONG WITH MORE OF AN INVERTED TROUGH EXTENDING NORTHWEST FROM THE LOW THROUGH WESTERN WISCONSIN. GFS ENSEMBLE DATA IS SIMILAR TO THE ECMWF. ONE THING FOR SURE IS THAT WESTERN AREAS OF THE FA WILL BE COLDER ON WEDNESDAY WITH HIGHS ONLY IN THE LOWER TO MIDDLE 30S. CONTINUED WITH A CHANCE OF RAIN ON TUESDAY...MIXING WITH AND THEN CHANGING TO SNOW BY WEDNESDAY MORNING. RIDGING ALOFT/SURFACE HIGH PRESSURE THEN BUILD VERY SLOWLY EASTWARD FROM THE NORTHERN ROCKIES TO THE FA IN THE THURSDAY THROUGH SUNDAY PERIOD. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ RAH/JPR mn AREA FORECAST DISCUSSION...UPDATED AVIATION SECTION NATIONAL WEATHER SERVICE UPTON NY 715 AM EST SUN NOV 12 2006 .NEAR TERM (TODAY)... AT 8Z WATER VAPOR AND 500MB RUC ANALYSIS SHOWED 500MB LOW HAD FINALLY CUTOFF OVER SOUTHERN WEST VIRGINIA...WITH AN INTENSE VORTICITY MAXIMA OVER WESTERN SOUTH CAROLINA (40 VORTICITY UNITS ACCORDING TO THE RUC...IMPRESSIVE)...AND AT THE SURFACE A BROAD AREA OF LOW PRESSURE CENTERED OVER SOUTH CENTRAL VIRGINIA...WITH 2.4 MB PRESSURE FALLS OVER THE PAST 3 HOURS OVER EAST CENTRAL NORTH CAROLINA. CONVECTION DEVELOPING OFF THE NORTH CAROLINA COAST AND POSITIVE VORTICITY ADVECTION FROM THE 500 MB LOW/VORTICITY MAXIMUM WILL CONTINUE TO SUPPORT PRESSURE FALLS NEAR THE EAST CENTRAL NORTH CAROLINA COAST...AND SHOULD LEAD TO COASTAL LOW FORMATION BETWEEN CAPE HATTERAS AND CAPE LOOKOUT NC THIS MORNING. THIS DATA BASED FORECAST IS IN STRONG AGREEMENT WITH THE 0Z/6Z NAM/0Z NGM AND TO A LESSER EXTENT THE 0Z ECMWF AND 3Z SREF ENSEMBLE MEAN (BOTH ARE A LITTLE NORTH OF CAPE HATTERAS WITH THEIR COASTAL LOW AT 12Z THIS MORNING). THE 0Z GFS DEVELOPS THIS LOW NEAR THE SOUTHEAST VIRGINIA COAST THIS MORNING...AS DO THE 0Z UKMET AND CANADIAN (BUT A TAD FURTHER SW). BASED ON THE DATA SUPPORTING THE NAM/NGM AND TO A LARGE DEGREE ECMWF/SREF ENSEMBLE MEAN SOLUTIONS...HAVE USED THE NAM FOR TIMING THE ONSET OF PRECIPITATION (ALSO NOTING THAT IT DID A VERY GOOD JOB CAPTURING THE BATCH OF SHOWERS WITH ISOLATED THUNDERSTORMS THAT MOVED CROSS THE EAST FORK OF LONG ISLAND/FAR SOUTHEAST CT OVERNIGHT). BASED ON THIS...AND THE LATEST RADAR TRENDS SHOWING NO EASTWARD PROGRESS (ACTUALLY SLIGHT WESTWARD DRIFT) TO RAIN SHIELD OVER CENTRAL PA/NY...EXPECT MOST PRECIPITATION TO HOLD OF UNTIL THIS AFTERNOON...SO ONLY HAVE SLIGHT CHANCE POPS TO START THIS MORNING...INCREASING TO CHANCE POPS BY LATE MORNING (HIGHEST WEST)...THEN CATEGORICAL POPS THROUGHOUT THIS AFTERNOON. HAVE SLIGHT CHANCE OF THUNDER IN THIS MORNING OVER EASTERN AREAS...NOTING THAT WE ALREADY HAVE HAD THUNDER OVERNIGHT...AND ALL MODELS SHOW SUB ZERO SHOALWATER INDICES (SUPPORTING ELEVATED CONVECTION)...AND LIFTED INDICES NEAR ZERO THIS MORNING. DEVELOPING SOUTHEAST TO EAST BOUNDARY LAYER FLOW THIS AFTERNOON...WILL BRING IN A SUFFICIENT MARINE LAYER TO PREVENT DEEP CONVECTION (AS SHOWN BY ALL MODELS INCREASING THE SHOALWATER INDEX TO ABOVE 0 AND MOST ABOVE 2 THIS AFTERNOON). AS FAR AS TEMPERATURES GO ALL BUT ORANGE/WESTERN PASSAIC COUNTIES ALREADY HAVE TEMPERATURES AROUND 60...SO USED WARMEST AVAILABLE GUIDANCE FOR HIGHS. EXPECT TEMPERATURES TO GENERALLY RISE 3-5 DEGREES FROM CURRENT LEVELS BEFORE ONSET OF STEADIER PRECIPITATION THIS AFTERNOON...SO IN THE HOURLY TEMPERATURES HAVE TEMPERATURES PEEKING AROUND MIDDAY...THEN STEADY OR SLOWLY FALLING DURING THE AFTERNOON. HAVE QUITE A LARGE NUMBER OF OBSERVATIONS OF VISIBILITIES OF 2 MILES OR LESS...SO HAVE PATCHY FOG IN THE ZONES THIS MORNING. AS SOUTHEAST TO EAST FLOW SETS UP AND STRENGTHENS BY THIS AFTERNOON IN THE BOUNDARY LAYER THE FOG SHOULD MIX OUT...BUT THIS SHOULD PROMOTE PATCHY DRIZZLE IN THE AFTERNOON (ESPECIALLY OVER LONG ISLAND AND COASTAL CT) WHEN IT IS NOT RAINING. && .SHORT TERM (TONIGHT THROUGH WEDNESDAY)... WHILE I INITIALLY PREFER THE NAM WITH STORM TRACK...OVER TIME IT BECOMES THE SLOWEST IN LIFTING THE STORM TO THE NORTH...AND HAS BEEN IN THE PAST FEW RUNS SLIGHTLY ACCELERATING ITS SOLUTION AND SHIFTING IT FURTHER WEST. THIS IS STILL TRUE WITH THE 6Z NAM...WHICH IS FURTHER WEST AND NORTH THAN THE 0Z NAM AT 0Z WEDNESDAY. THE GFS REMAINS THE FASTEST MODEL LIFTING NORTH...AND IS AN OUTLIER IN THIS...SO HAVE DISREGARDED IT. THE 0Z UKMET/ECMWF/3Z SREF ENSEMBLE MEAN ARE A REASONABLE SOLUTION IN TERMS OF SPEED (THOUGH THE ECMWF IS FURTHER EAST THAN THE OTHER 2...ALSO FURTHER EAST THAN THE 6Z NAM)...SO FOLLOWED THE 12Z UKMET/3Z SREF FOR THE LOW TRACK BY TUESDAY MORNING. CURRENTLY EXPECT THE LOW TO BE CENTERED SOUTH OF MONTAUK POINT TUESDAY MORNING...THEN LIFT NORTH ACROSS/JUST TO THE EAST OF FAR EASTERN PORTIONS OF THE CWA TUESDAY MORNING/EARLY TUESDAY AFTERNOON. THIS LOW TRACK MADE NECESSARY CHANGES TO THE CURRENT FORECAST. THE MAIN CHANGE IS THE SHIFT OF THE AXIS OF QPF TO THE EAST. WHILE EXACT DETAILS ARE IN THE HYDROLOGY SECTION...THIS RESULTS IN DROPPING THE FLOOD WATCH. EXPECT PERIODS OF RAIN THIS AFTERNOON AND EVENING WITH PATCHY DRIZZLE AS THE TROUGH ASSOCIATED WITH THE DEVELOPING COASTAL LOW CROSSES THE AREA...THEN EXPECT A LULL FROM LATE TONIGHT INTO MONDAY MORNING AS THE COASTAL LOW CONSOLIDATES AND LIFTS SLOWLY NORTH AND EAST. HAVE LOWERED POPS TO CHANCE DURING THIS TIME...AS IT WILL BE MAINLY PREDOMINATED BY DRIZZLE. INCREASE POPS TO LIKELY MONDAY AFTERNOON AND NIGHT AS COASTAL LOW GETS BETTER ORGANIZED AND DRAWS NEAR. FOCUS LIKELY POPS TUESDAY MORNING (IN COLLABORATION WITH SURROUNDING OFFICES) OVER EASTERN AREAS TUESDAY MORNING AS LOW PASSES WITH CHANCE POPS EAST...THEN CHANCE POPS TUESDAY AFTERNOON (REFLECTING UNCERTAINTY IN TIMING/EXACT TRACK OF LOW)...THEN SLIGHT CHANCE POPS TUESDAY EVENING (EXCEPT LOW CHANCE POPS FAR EAST (CLOSEST TO LOW)...THEN SLIGHT CHANCE POPS AFTER MIDNIGHT TUESDAY NIGHT...ALSO REFLECTING UNCERTAINTY IN APPROACH OF NEXT SYSTEM. AS FAR AS TEMPERATURES TODAY THROUGH TUESDAY NIGHT FOLLOWED A BLEND OF AVAILABLE GUIDANCE. MADE NO CHANGES TO THE FORECAST ON WEDNESDAY...AS SOUTHERLY FLOW SETS UP OVER THE REGION AHEAD OF THE NEXT SYSTEM WHICH SHOULD BE LOCATED OVER THE UPPER OHIO RIVER VALLEY/LOWER GREAT LAKES BY WEDNESDAY EVENING. && .LONG TERM (WEDNESDAY NIGHT THROUGH SATURDAY)... 0Z ECMWF/GFS IN REASONABLE DEGREE OF AGREEMENT OVER MEDIUM RANGE...REFLECTING THE SET UP OF A TROUGH OVER THE EASTERN US BY THE END OF THIS WEEK...THE FORECAST IN GENERAL REFLECTS THIS...SO COUPLED WITH MORE PRESSING SHORT TERM CONCERNS...MADE NO CHANGES TO THE EXTENDED FORECAST. && .AVIATION... WIDESPREAD LIFR CONDITIONS ACROSS THE AREA AS OF 12Z...WITH SOME LOCATIONS INCLUDING JFK AND LGA REPORTING VLIFR IN DENSE FOG. EXPECT GRADUAL IMPROVEMENT TO IFR BY MID TO LATE MORNING. IFR CONDITIONS ARE LIKELY TO CONTINUE THEREAFTER THROUGH 12Z MON...AS SATURATED LOW/MID LEVELS WILL NOT ALLOW MUCH INCREASE OF CIG HGTS TODAY. RAIN WILL BE DEVELOPING DURING THE DAY...LIKELY BECOMING WIDESPREAD IN THE AFTERNOON. THE RAIN COULD BE HEAVY AT TIMES DURING THE AFTERNOON AND EVENING WITH CIGS/VSBYS DROPPING DOWN INTO THE LIFR CATEGORY AT TIMES. STEADY RAIN WILL GIVE WAY TO MORE OF A DRIZZLE SITUATION LATE TONIGHT...BUT EXPECT IFR OR LOWER CONDITIONS TO CONTINUE. LGT/VRBL WINDS WILL BECOME E THEN NE THIS MORNING. SPEEDS WILL RANGE FROM 6-12 KT. NE FLOW WILL INCREASE A BIT TONIGHT INTO THE 10-15 KT RANGE. && .MARINE... WIND FCST REMAINS DIFFICULT AS 00Z MODELS CONTINUE TO PRESENT A VARIETY OF SOLUTIONS WITH RESPECT TO THE PLACEMENT AND INTENSITY OF LOW PRESSURE ALONG THE MID ATLANTIC COAST DURING THE NEXT 24-48 HOURS. BASICALLY THE GFS IS FASTEST TO MOVE THE SFC LOW NORTHWARD INTO NEW ENGLAND...THEN NAM IS THE SLOWEST AND FURTHEST OFFSHORE...AND THE UKMET AND ECMWF ARE IN BETWEEN. THIS RESULTS IN QUITE A BIT OF SPREAD FOR THE MODEL WIND FCSTS. MOSTLY WENT CLOSE TO THE NAM...BUT ADJUSTED DIRECTIONS/SPEEDS SOMEWHAT TO FIT BETTER WITH THE OTHER MODELS AND SURROUNDING OFFICES. RESULT IS NE FLOW DEVELOPING TODAY...THEN INCREASING TONIGHT AND REMAINING RATHER BRISK ON MON. THE PERSISTENT NE FLOW WILL CAUSE SEAS TO BUILD REACHING 6 TO 9 FT MON AND MON NIGHT. FLOW GRADUALLY BACKS TO NORTH ON TUE AS THE LOW PASSES BY...LIKELY JUST TO THE EAST OF THE LOCAL WATERS. THIS WILL ALLOW SEAS TO SUBSIDE. BASED ON THE ABOVE FCST...NO CHANGES ARE NEEDED TO THE EXISTING SCA FOR THE OCEAN ZONES...WHICH RUNS THROUGH TUE AFTERNOON. LONG PERIOD OF BRISK NE FLOW WILL CAUSE WATER TO PILE UP IN WESTERN LONG ISLAND...AS WELL AS IN NY HARBOR AND THE BACK BAYS OF THE LONG ISLAND SOUTH SHORE. FORTUNATELY ASTRONOMICAL TIDES ARE RELATIVELY LOW FOR THE NEXT COUPLE OF DAYS...AND 2.5 TO 3 FOOT DEPARTURES WILL BE NEEDED TO REACH MINOR COASTAL FLOODING THRESHOLDS. CURRENT GUIDANCE SUGGESTS THAT WE WILL PROBABLY REMAIN BELOW THOSE LEVELS AT MOST LOCATIONS...AND ANY COASTAL FLOODING WOULD BE ISOLATED AND MINOR AT WORST. GREATEST POSSIBILITY FOR ANY FLOODING THAT MIGHT OCCUR WOULD LIKELY BE DURING THE MON AFTERNOON AND LATE MON NIGHT HIGH TIDE CYCLES. WILL NEED TO CONTINUE MONITORING OVER THE NEXT COUPLE OF DAYS. && .HYDROLOGY... EXPECTED STORM TRACK SHIFTS THE AXIS OF HEAVIEST QPF OVER THE NEXT 48 TO 60 HOURS EASTWARD OVER CONNECTICUT AND LONG ISLAND. THIS IS THE AREA OVER WHICH ALL MODELS CURRENTLY AGREE WILL RECEIVE 1 TO 1.5 INCHES OF RAIN. TO THE WEST...MODELS GENERALLY AGREE ON 0.75 TO 1 INCH OF RAIN OVER THE CURRENT FLOOD WATCH AREA. THIS IS MUCH LESS (BY A FACTOR OF 75 TO 100 PERCENT) THAN CURRENT 12-24 HOUR FLASH FLOOD GUIDANCE OVER NORTHEAST NEW JERSEY AND THE LOWER HUDSON VALLEY...SO I HAVE OPTED TO CANCEL THE FLOOD WATCH THERE (IN COLLABORATION WITH MT HOLLY). THE EXPECTED RAINFALL OVER CONNECTICUT AND LONG ISLAND IS ALSO 75 TO 100 PERCENT BELOW FLASH FLOOD GUIDANCE...SO THERE WAS NO NEED (IN COLLABORATION WITH SURROUNDING OFFICES) TO PUT THOSE AREAS IN A WATCH. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NJ...NONE. NY...NONE. MARINE...SMALL CRAFT ADVISORY FOR ANZ350-353-355 UNTIL 5 PM TUESDAY. && $$ PUBLIC/HYDROLOGY...MALOIT AVIATION/MARINE...CNJ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 1210 PM EST SUN NOV 12 2006 .SHORT TERM /REST OF TODAY/...SURFACE LOW PRES AND ASSOCIATED COLD FRONT ARE LIFTING NEWD OFF THE NRN OBX LATE THIS MORNING WITH THE UPPER LOW ACROSS CENTRAL NC. A WIDE AREA OF WRAP AROUND RAINFALL IS CONTINUING ACROSS MUCH OF THE WESTERN PORTION OF THE CWA. TEMPERATURES HAVE FALLEN INTO THE 50S BEHIND THE FRONT AND WINDS HAVE INCREASED UP TO 15 MPH WITH GUSTS 25-30 MPH AS STRONG CAA HAS COMMENCED. THE LOW PRES WILL SLOWLY LIFT NEWD THIS AFTERNOON WITH THE WRAP AROUND RAINFALL SLOWLY ENDING ACROSS THE SERN PORTION OF THE CWA THIS AFTERNOON. LOW PRES WILL BE SLOW TO PUSH EAST OF THE VA CAPES TODAY AND TONIGHT AS THE UPPER LOW BECOME CUTOFF ALLOWING FOR WRAP AROUND RAINFALL TO CONTINUE ACROSS NERN NC THIS AFTERNOON AND EVENING...WITH COVERAGE DIMINISHING THIS EVENING. UPDATED THE ZONES AND GRIDS TO CAPTURE CURRENT PCPN AND TEMPERATURE TRENDS. && .AVIATION...WIDESPREAD MVFR CONDITIONS WITH AREAS OF IFR WILL PREVAIL THIS AFTN INTO THIS EVENING...GRADUALLY IMPROVING LATE TONIGHT AND MON. && .MARINE...SIGNIFICANT UPDATE THIS MORNING AS SFC LOW TRACKED FARTHER S THAN FCST AND SW WINDS NEVER REACHED GALE FORCE. RUC HAD BEST HANDLE ON SFC LOW AND WINDS 12-15Z AND LEANED TO IT FOR UPDATE THROUGH EARLY THIS EVENING. NOW EXPECT GALES (MAINLY IN GUSTS) TO SPREAD OVER WATERS FROM S TO N THIS AFTN AS SFC LOW GRADUALLY MOVES NE AND CAA KICKS IN BEHIND IT. EXTENDED GALES TO ALL WATERS (EXCEPT SCA FOR SOUNDS) AND IN TIME TO 06Z TONIGHT. ADJUSTED SEAS FOR CURRENT BUOY OBS OF 6-9 FT...WW3 IS UNDERDONE. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST MONDAY FOR AMZ130-135. GALE WARNING UNTIL 1 AM EST MONDAY FOR AMZ152-154-156-158. GALE WARNING UNTIL 1 AM EST MONDAY FOR AMZ150. && $$ SHORT TERM...KENNEDY AVIATION...MERRELL MARINE...MERRELL nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 745 PM CST SUN NOV 12 2006 .CURRENT OBSERVATIONAL OVERVIEW... 01Z SURFACE ANALYSIS DEPICTED RIDGE AXIS OVER THE CENTRAL DAKOTAS WITH PRESSURE RISE MAXIMA FROM CENTRAL NEBRASKA INTO SOUTHEAST NORTH DAKOTA. LATEST WATER VAPOR IMAGERY SHOWED MEAN POSITIVELY TILTED 500MB TROUGH FROM THE CENTRAL DAKOTAS WITH MAIN JET ENERGY ON THE DOWNWIND SIDE OF FEATURE OVER EASTERN MINNESOTA. EXAMINATION OF SATELLITE IMAGERY SHOWED BAND OF STRATUS (MVFR CIGS) LIFTING NORTHEAST AHEAD OF EASTWARD ADVANCING TROUGH. .FORECAST DETAILS.(OVERNIGHT)... MAIN FORECAST CHALLENGE OVERNIGHT CONCERNS CLOUD TRENDS AND RESULTANT LOW TEMPERATURES. LATEST RUC MODEL HAS GOOD HANDLE OF SURFACE AND UPPER LEVEL FEATURES. MODEL TAKES SURFACE RIDGE AXIS EAST OVER CWFA WITH FEATURE JUST TO THE EAST OF THE VALLEY BY 09Z. GOOD DEEP LAYERED DRY COLUMN WITH SYSTEM POINTS TO SKIES BECOMING MAINLY CLEAR OVERNIGHT WITH ONLY EXCEPTION IN THE BJI AREA WHERE RESIDUAL BOUNDARY LAYER H2O ATTM COULD BECOME ENTRENCHED BENEATH STRENGTHENING NOCTURNAL LOW LEVEL INVERSION OVERNIGHT. BASED ON THIS AGREE WITH DAYCREW THAT WARMEST LOWS OVERNIGHT WILL BE ACROSS EASTERN MOST ZONES. UPDATED PLANNED BY MID-EVENING TO ADDRESS RESIDUAL LOW POPS OUT EAST AND JUST OVERALL COSMETIC CHANGES. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ BERG nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 100 PM CST SUN NOV 12 2006 .UPDATE... TEMPERATURES WARMER THAN EXPECTED IN CLEAR SKY AREAS... AND COOLER IN CLOUDY REGIONS. SUNNY SKIES IN SOUTHEAST NORTH DAKOTA AND NORTHWESTERN MINNESOTA WITH CLOUDY SKIES SURROUNDING. CURRENTLY SURFACE BOUNDARY IS ALONG HALLOCK-GRAND FORKS-OAKES LINE AND MOVING EAST. SKY COVER IS EXPECTED TO INCREASE FOLLOWING THIS LINE. WINDS WILL ALSO SHIFT FROM SOUTH TO NORTHWEST FOLLOWING THE BOUNDARY. CHALLENGES WERE THE TIMING OF THE CLOUD COVER CHANGES AND CORRESPONDING TEMPERATURES. RUC IS HANDLING CURRENT CONDITIONS THE BEST... PARTICULARLY THE SKY COVER AND SURFACE TEMPERATURES. MOS GUIDANCE AND NAM SURFACE TEMPERATURES WERE NOT HOLDING TRUE FOR CURRENT OBSERVATIONS. CLOUD COVER FOR FIRST PART OF FORECAST IS MORE CERTAIN THAN FOR LATER HOURS. GFS AND HPC BOTH SHOW SOME PRECIPITATION POSSIBLE IN THE SOUTHEAST FORECAST AREA BUT CLEARING CONDITIONS DO NOT SUPPORT THIS. TOOK OUT AFTERNOON PRECIPITATION CHANCES ACCORDINGLY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ STEINBRUCKNER/GODON nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1035 AM EST SUN NOV 12 2006 .SHORT TERM /REST OF TODAY/... UPPER LOW ABOUT WHERE IT WAS EXPECTED TO BE BASED ON PREVIOUS MODEL RUNS THIS MORNING...OVER THE NORTH CAROLINA PIEDMONT. SAID FEATURE SHOULD CONTINUE TO MOVE SOUTH AND EAST WITH TIME. SURFACE FRONTAL BOUNDARY AT THE COAST. SATELLITE IMAGERY SHOWS EXTENSIVE CLOUDINESS HUGGING THE TENNESSEE BORDER AREAS...AND SOME OF THE INTERIOR MOUNTAINS BUT MOST OF THE NON-TERRAIN AREAS MOSTLY CLEAR. MORNING OBSERVATIONS FROM THE MOUNTAINS REVEALED A LIGHT SNOW FELL IN THE VERY LATE HOURS OVERNIGHT FOR THE VERY HIGHER ELEVATIONS...WITH ONE INCH REPORTED FROM BEECH MOUNTAIN...MOUNT MITCHELL...GRANDFATHER AND AS FAR SOUTH AS FLAT TOP MOUNTAIN IN SOUTHEAST BUNCOMBE COUNTY. ALMOST NO SNOW REPORTED FROM THE VALLEYS. HOWEVER...LAPS SOUNDINGS AND FORECAST SOUNDINGS REVEAL THE SATURATED LAYER IS NOT VERY DEEP AND THE 85H TEMPERATURES SHOULD BE RISING THROUGH THE AFTERNOON. SATELLITE TRENDS REVEAL SLOW EROSION OF THE ANCHORED CLOUD DECK HAS ALREADY BEGUN...BUT THE LOW CLOUDS MAY HANG ON FOR MOST OF THE AFTERNOON. SO...ANY LINGERING SNOW AT THIS HOUR SHOULD TRANSITION TO ALL RAIN BY EARLY AFTERNOON. NEITHER RUC NOR 06Z NAM/WRF PRODUCES MUCH MORE ADDITIONAL PRECIPITATION FOR THE TENNESSEE BORDER AREAS. WE WILL HOLD ON TO ISOLATED RAIN SHOWERS FOR THE NORTHERN MOUNTAINS...HOWEVER...THIS AFTERNOON. MOUNTAIN WINDS HAVE GUSTED AS HIGH AS 40 TO 45 MPH SO FAR; KAVL JUST HAD A WIND GUST TO 43 MPH. THE BETTER MIXING HAS ALSO RESULTED IN STRONG GUSTS FOR THE FOOTHILLS AND PIEDMONT; KCLT RECENTLY GUSTED TO 31 MPH. WITH TIME...THE WINDS THROUGH THE ATMOSPHERIC COLUMN SHOULD WANE...AND ANY RESIDUAL COLD ADVECTION WILL BE REPLACED BY WARM ADVECTION. FOR NOW...WILL NOT PLAN ANY CHANGES TO CURRENT WIND ADVISORY/LAKE WIND ADVISORY PRODUCTS FOR THE HIGHER TERRAIN. BASED ON CHANGES WE MADE TO THE FOOTHILL/PIEDMONT WINDS FOR THE AFTERNOON...WILL HAVE TO CARVE OUT SOME OF TEH LARGER ZONE GROUPINGS TO INCREASE TO BREEZY BUT WILL HOLD OFF ON ANY EXTENSION OF THE LAKE WIND ADVISORY AND MONITOR FOR POTENTIAL UPDATES LATER. TEMPERATURES HAVE RISEN STEADILY THIS MORNING...BUT LOW LEVEL THICKNESS SCHEME SUPPORTS NO MORE THAN LOWER 60S FOR THE CWFA...AND NORTHEAST CWFA WILL BE IN THE OUTER CIRCULATION OF THE UPPER LOW FOR A WHILE YET. MOUNTAINS MAY SEE MINIMAL MERCURY CLIMBS TODAY. WILL LOWER MAXES CWFA-WIDE...TO MID/UPPER 50S FOOTHILLS AND PIEDMONT...AND HOLD ON TO LOWER 60S ONLY FOR THE EXTREME SOUTHWEST CWFA. && .PREV DISCUSSION... /ISSUED 255 AM EST SUN NOV 12 2006/ SHORT TERM /TODAY THROUGH TUESDAY NIGHT/... PCPN CHANCES THIS MORNING WILL BE LIMITED TO JUST THE NC MTNS...AND MAINLY THE WESTERN SLOPES AND HIGHER ELEVATIONS AS A PERIOD OF BRISK UPSLOPE FLOW CONTINUES. LLVL MOISTURE IS QUITE SHALLOW AND THE TEMPERATURES WITHIN THIS MOIST LAYER...MARGINALLY COLD...PERHAPS -2C AT BEST. SO...A MIX OF SPOTTY LIGHT RAIN/SNOW SHOWERS AND PATCHY DRIZZLE/FREEZING DRIZZLE WILL BE SEEN THIS MORNING WITH PROGRESSIVE LLVL DRYING SLATED FOR THIS AFTERNOON. BASED ON PALTRY MAGNITUDE OF EXPECTED WINTER WX THREAT AND RECENT RECORD WARMTH...LITTLE IF ANY SNOW OR ICE ACCUMULATION IS EXPECTED. WITHIN THE SUBSIDING AIRMASS TODAY...GUSTY WINDS WILL CONTINUE. 40-50 MPH GUSTS ARE EXPECTED ACRS FAVORED AREAS OF THE NC MTNS WITH CONDITIONS VARYING BETWEEN SOME DEGREE OF WINDY AND BREEZY ELSEWHERE. PRESSURE GRADIENT REMAINS UP TONIGHT...SO A MIXED AIRMASS WILL CONTINUE UNDER MAINLY CLEAR SKIES AS S/WV RIDGING ALOFT BUILDS A TOP THE CWFA. SHORT WAVE RIDGE REMAINS ACROSS THE AREA MONDAY. THE RIDGE MOVES EAST MONDAY NIGHT AS WEAK SHORT WAVE MOVES THRU INTRODUCING NEAR ZONAL FLOW AND MORE WEAK SHORT WAVES FOR TUESDAY. STRONG WAVES DIG A TROF OVER THE CENTRAL PART OF THE COUNTRY TUESDAY NIGHT WHILE OUR FLOW BECOMES SOUTHWESTERLY. AT THE SURFACE...CWFA WILL BE BETWEEN DEPARTING LOW AND HIGH PRESSURE MOVING IN FROM THE WEST. SHORT WAVE WILL BRING SOME CIRRUS FOR MONDAY AFTERNOON AND EVENING...BUT LOW LEVELS VERY DRY. THE DRY LOW LEVELS CONTINUE TUESDAY...BUT COULD BE QUITE A BIT OF CIRRUS STREAMING EASTWARD SO PARTLY CLOUDY SKIES. NEXT SYSTEM APPROACHES THE AREA TUESDAY NIGHT. NAM BRINGS PRECIP TO THE MOUNTAINS...WHILE GFS KEEPS IT TO THE WEST. SHORT RANGE ENSEMBLES SHOW SOME PRECIP POSSIBLE OVER THE MOUNTAINS SIMILAR TO NAM...BUT PLUME DIAGRAMS SHOW MANY DRY MEMBERS. MEMBERS SHOWING PRECIP...EXCEPT FOR ONE...HAVE ONLY LIGHT AMOUNTS. CANADIAN IS EVEN SLOWER THAN THE GFS. THEREFORE HAVE DECIDED TO SLOW PRECIP WITH ONLY CHC TO SLIGHT CHC OVER THE MOUNTAINS. HIGHS RETURN TO ABOVE NORMAL LEVELS WITH RIDGING ON MONDAY. LOWS BELOW NORMAL MONDAY NIGHT WITH SOMEWHAT DECENT RADIATIONAL CONDITIONS. HIGHS ABOVE NORMAL AGAIN TUESDAY...BUT A LITTLE LOWER WITH SLIGHTLY LOWER THICKNESSES AND INCREASING CIRRUS. LOWS TUESDAY NIGHT NEAR NORMAL. LONG TERM /WEDNESDAY THROUGH SATURDAY/... GFS AND CANADIAN SLOWING SYSTEM FOR WEDNESDAY. STILL LOOKS LIKE A DECENT CHANCE OF PRECIP OVER THE MOUNTAINS WEDNESDAY...SO WILL LEAVE POP AS IS. WILL HAVE TO WATCH THE DEVELOPMENT OF THIS SYSTEM. GFS SHOWS QUITE A BIT OF FORCING WITH HIGH SHEAR. FORECAST INSTABILITY QUITE LOW OVER OUR CWFA...BUT THIS FITS THE PATTERN FOR A FALL SEVERE WEATHER EPISODE. THAT SAID...STILL TOO EARLY TO FOR BANDWAGON JUMPING. SCATTERED SHOWERS SHOULD CONTINUE ACROSS THE NC MOUNTAINS...AND NORTHERN NC FOOTHILLS AND PIEDMONT THROUGH THURSDAY MORNING AS DRY SLOT MOVES IN TO THE AREA FROM THE SOUTHWEST. A DECENT THICKNESS PACKING ASSOCIATED WITH UPPER TROF WILL CROSS THE AREA WEDNESDAY AND A DEEP THERMAL TROF WILL SLOWLY TRANSIT THE CWFA THROUGH FRIDAY. TEMPERATURES ASSOCIATED WITH THIS SCENARIO WILL GENERALLY BE ON THE ORDER OF 10 DEGREES BELOW NORMAL THURSDAY THROUGH SATURDAY. AVIATION... LINGERING STRATOCU ACRS THE PIEDMONT WILL CONTINUE TO SCOUR DURING THE PRE-DAWN HOURS...WITH UPVALLEY CLOUDS AT KAVL LINGERING A LITTLE LONGER...PERHAPS UNTIL 12 UTC. OTHERWISE...SOLE CONCERN FOR THE 06 UTC TAF PACKAGE WILL BE GUSTY NW WINDS WHICH WILL BE SEEN PRETTY MUCH ALL DAY. EXPECT WIND GUSTS TO ABOUT 20 KTS ACRS LOWER ELEVATIONS AND TO ABOUT 30 AT KAVL...DIMINISHING BY THIS EVENING. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...LAKE WIND ADVISORY FOR GAZ010-017 UNTIL 7 PM SUNDAY. NC...WIND ADVISORY FOR NCZ033-034-048>050-052>055-059-063>066-501- 503-505-507-509 UNTIL 7 PM SUNDAY. ...LAKE WIND ADVISORY FOR NCZ051-058-062 UNTIL 7 PM SUNDAY. SC...LAKE WIND ADVISORY FOR SCZ001 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR SCZ002-003 UNTIL 7 PM SUNDAY. && $$ SHORT TERM...44 sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 908 PM EST SUN NOV 12 2006 .SHORT TERM /REST OF TONIGHT/... LAST SEVERAL STLT IR IMAGES SHOW VERY LITTLE MOVEMENT WITH THE LOW PRESSURE CENTER E OF THE VA CAPES. MEANWHILE...RADAR LOOPS SHOW ONE MAIN SWIRL OF ENHANCED RAINFALL ON THE BACK-SIDE...AFFECTING ERN VA AND NERN NC. DYNAMICALLY SPEAKING...AS THIS LOW CONTINUES TO DEEPEN/CUTOFF...THERMAL/MOISTURE ADVECTIONS AND ISENTROPIC ASCENT ON THE BACKSIDE CONTINUE TO DIMINISH. THE RESULT IS RAIN BANDS DIMINISHING IN COVERAGE AND IN AREAL EXTENT...AS DRIER AIR IS WRAPPING AND BROADENING IN BTWN THE BANDS. OVERNIGHT...DYNAMICAL FORCING WILL CONTINUE TO DIMINISH AS THE MID/UPPER LOW SHIFTS SLOWLY EAST. WILL LIKELY SCALE BACK WITH POPS OVERNIGHT...ESPECIALLY IN WRN ZONES...AS THE AIRMASS DRIES OUT ABOVE THE LOWER LEVELS. RUC FCST SOUNDINGS IN FACT WOULD SUPPORT MORE DRIZZLE THAN ANYTHING ELSE LATE...GIVEN THE ABSENCE OF MOISTURE (AND ICE NUCLEI AVAILABILITY) ABOVE THE -10C ISOTHERM. .MARINE FCST...WILL HAVE CURRENT GALE WARNINGS DOWNGRADED TO SMALL CRAFT ADVISORIES BY OR BEFORE MIDNIGHT OVER ALL BUT THE SRN CSTL WATERS. COMPLICATING MATTERS CURRENTLY IS THE CLOSE PROXIMITY OF THE CSTL WATERS TO THE LOW CENTER...WHICH IS CAUSING QUITE A VARIANCE IN WIND DIRECTION OVER A RELATIVELY SMALL REGION...AS WELL AS MUCH LIGHTER SPEEDS COMPARED TO AREAS JUST TO THE WEST WHERE THE GRADIENT REMAINS THE STRONGEST. .HYDROLOGY...WIDESPREAD 2-3 INCHES OF RAIN OVER THE FCST AREA...WITH MANY POCKETS OF 3-4 INCHES...IS CAUSING A RISE IN RIVER LEVELS ACROSS THE APPOMATTOX AND ESPECIALLY THE CHOWAN RIVER BASINS. THE LATEST GAUGE FORECASTS FROM THE RFC SUGGEST THE LOWER JAMES AND APPOMATTOX BASINS WILL REMAIN BELOW FLOOD STAGE (FEW SITES IN THE APPOMATTOX BASIN MAY GET CLOSE TO FS)...HOWEVER WILL BE ISSUING ADDITIONAL RIVER FLOOD WARNINGS OVER PORTIONS OF THE CHOWAN BASIN...WHERE SOME MINOR FLOODING IS EXPECTED. && .PREV DISCUSSION... (ISSUED 428 PM EST SUN NOV 12 2006) SHORT TERM /REST OF TONIGHT/... WL BE RAISING SHORTLIVED WND ADVSRY FOR SE VA BASED ON CONTD STRENGTHENING OF NNW SFC WNDS AS STM JUST E OF MOUTH OF BAY INTENSIFIES. XPCTG GUSTS TO 45 TO 50 MPH THESE AREAS THROUGH 00Z/13. PREV DISCUSSION... (ISSUED 311 PM EST SUN NOV 12 2006) SHORT TERM /TONIGHT THROUGH TUESDAY/... WHAT A DIFF A DAY MAKES...BASKED UNDER SNY/WRM CONDS YDA...NOW SGFNTLY COOLER W/ GSTY NNW WNDS AND WDSPRD RA. NR VERTICALLY STACKED LO PRES (SFC-ALOFT) WL BE TRACKING THROUGH VA CAPES THIS EVE...THEN CONT SLOLY E LT TNGT...THEN MR NNE MON/MON NGT (TWD XTRM SE NEW ENG). WATCHING LLVL SURGE FM NNW PAST CPL HRS...SPDS NOW GSTY TO 40-50 MPH ACRS PTS OF ERN VA. SFC LO PRES CONTG TO STRENGTHEN...DOWN TO JUST BLO 1000MB PRES NR MOUTH OF BAY. ADDTNL RA SPIRALING WWD INTO FA ATTM...WL BE KPG POPS AT 100% ACRS FA THROUGH THE EVE HRS...B4 PCPN GRDLY SHIFTS TO THE CST AFT MDNGT. WL CONT HVY RA MENTION FOR ERN SXNS OF FA THIS EVE. W/ MR NNE MVMNT XPCTD TO STM MON/MON NGT...CLDS AND EVEN PCPN WL BE STUBBORN TO EXIT (ESP TWD THE CST). DRYING/WRMG XPCTD DURG TUE AS STM LIFTS THROUGH XTRM ERN NEW ENG AND LLVL FLO (HERE) BCMS SSW. LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... PD OF TRANQUIL WX SHORTLIVED TUE NGT THROUGH WED...B4 NEXT SGFNT AMPLIFICATION OF UPR LVL TROUGH (AND CORRESPONDING SFC LO PRES DVLPMNT) W OF MTNS BY LT WED/WED NGT. MDLS SUGG THAT NEXT STM WL BE SIMILAR TO THE ONE ONGOING NOW...HWVR...IT IS FCST TO "BOMB" WNW OF FA...INSTEAD NR THE MDATLC CST. XPCTG A STRNG CDFNT TO PUSH THROUGH FA THU...W/ AT LEAST SCTD SHRAS (ADDTNL MOD/HVY RA???)...THEN DRY/COOL WX FRI THROUGH NEXT WKND. AVIATION... BREEZY/WINDY THRU THE EVENG (ESP ACRS CSTL ZONES)...HAS BECOME MAINLY MVFR/VFR ACRS PIEDMNT...TO MAINLY IFR ALONG THE COAST. WINDS DECREASE AFTER MIDNIGHT ESP INLAND BUT CLDS TO CONTINUE OVERNGT. MARINE... COMPLEX SCENARIO CONTINUES THIS EVENING...SFC LOW NEAR THE VA/NC BORDER/CURRITUCK SND. SEEING GUSTS CLOSE TO GALE FORCE IN THE BAY RIGHT NOW. BASED ON THE TRACK OF THE SFC LOW WILL GO WITH GALES TONIGHT THRU 06Z LIKELY TRANSITIONING BACK TO SCAS AFT THAT TNGT. (SEAS ACTUALLY HIGHER NRN CSTL WTRS DUE TO NE FLOW UP THAT WAY). SMALL CRAFTS WILL CONTINUE IN NW FLOW THRU APPROX NOON MON ALL AREAS AND LINGERING A BIT LONGER N OF PARRAMORE DUE TO HIGHER SEAS. HYDROLOGY... WDSPRD 1-2" RA HAS OCCURRED SO FAR TDA...ESP INLAND VA/NE NC. BULK OF HVY RA XPCTD TO OCCUR FM I95 ON E TNGT. RVR STAGES WL RESPOND TO THIS MOD/HVY RA EVENT...XPCTG NEED FOR FLD WRNGS...ESP AT MATOACA...FRANKLIN AND PSBLY SEBRELL. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...GALE WARNING FOR ANZ630>633-650-652-654 UNTIL MIDNIGHT MONDAY. ...GALE WARNING FOR ANZ656-658 UNTIL 5 AM MONDAY. && $$ SHORT TERM UPDATE...HURLEY va AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BLACKSBURG VA 1235 PM EST SUN NOV 12 2006 .AVIATION... LOW PRESSURE TO THE SE COMBO WITH UPSLOPE FLOW WESTERN SLOPES WILL KEEP RANGE OF CONDITIONS FROM IFR/MVFR SE WVA SITES TO VFR/OCNL ELSWHERE INTO THIS EVENING. SPOTTY -RA MAY OCCUR AT LYH/DAN WITH SPORADIC -RA/-SN BLF BUT OVERALL EXPECTING ONLY BRIEF REDUCTIONS IN VSBY. HOWEVER GUSTY N/NW WINDS WILL PREVAIL INTO LATE THIS AFTERNOON WITH SOME GUSTS ABOVE 30 KTS POSSIBLE ACROSS THE EASTERN SITES. SYSTEM EXITS THE COAST OVERNIGHT ALLOWING SOME DRYING TO TAKE PLACE ESPCLY EAST WHILE EXPECTING LOWER CEILINGS TO FILL BACK IN SE WVA WHERE MVFR/IFR LIKELY FOR THE MOST PART. RESIDUAL CLOUDS SHOULD FINALLY BREAK ON MONDAY ALTHO LINGERING MVFR CEILINGS AT TIMES EARLY WITH WITH LOW LEVEL RH HANGING ACROSS THE EAST. && .PREV DISCUSSION... (ISSUED 950 AM EST SUN NOV 12 2006) SHORT TERM /REST OF TODAY/... LOW PRES ALONG THE FRONT CONTINUES TO DRIFT SLOWLY NE THRU EASTERN NC THIS MORNING WITH ONGOING NEGATIVE TILT PULLING LIGHT/MOD RAIN BACK ACROSS MUCH OF THE PIEDMONT ATTM. EXPECT AS THE SYSTEM WORKS NE THIS AFTERNOON WILL SEE DRY AIR SLOWLY CUTOFF -RA ON THE SW SIDE AS MID LEVEL AXIS OF CONVERGENCE PIVOTS MORE INTO THE NERN ZONES WHERE WILL KEEP CAT/LIKELY POPS GOING. ELSW ABRUPT DROPOFF IN RH LIKELY ALONG THE SOUTHERN BLUE RIDGE PER NW DOWNSLOPE/SUBSIDENCE BEFORE GETTING BACK INTO MORE UPSLOPISH MOISTURE WESTERN SLOPES. HOWEVER GIVEN FLOW ALOFT MORE NORTHERLY AND BEST MOISTURE OUT WITH COASTAL LOW APPEARS EVEN UPSLOPE MIX OF PRECIP LIKELY VERY LIGHT/SPOTTY THIS AFTERNOON. THIS SEEN IN MOST MODEL OUTPUT ESPCLY LATEST WRF/NMM AND RUC WHICH HAVE VERY LIMITED COVERAGE. THUS PLAN TO CUT POPS TO CHANCE WESTERN SLOPES AND GO WITH LITTLE OR NO PRECIP FROM THE NEW RIVER VALLEY SOUTH. WINDS HAVE BEEN BELOW ADVISORY LEVELS SO FAR WITH WAVE SLOW TO MOVE NE/DEEPEN AND RATHER WEAK 85H JET. EXPECT ONCE ITS GETS A BIT FARTHER EAST AND MIXING INCREASES WILL SEE RIDGES PICK UP ALTHO FORECAST PRES RISES NOT ALL THAT GREAT FOR THE AFTERNOON. OTRW SOME SMALL ADJUSTS TO TEMPS SINCE APPEARS ONLY SLIGHT RISES AT BEST MOST AREAS THRU THE AFTERNOON. PREV DISCUSSION... (ISSUED 647 AM EST SUN NOV 12 2006) AVIATION... BLF WILL START OUT WITH IFR CONDITIONS THIS MORNING DUE TO STRONG LOW LEVEL WINS PUSHING MOISTURE UP THE MOUNTAINS. CEILINGS WILL IMPROVE GRADULLY WITH CEILINGS AT BLF BECOMING MVFR BY THE END OF THE DAY. LOW PRESSURE DEVELOPING IN NORTH CAROLINA WILL KEEP VFR CLOUDS IN OVER LYH THROUGH THIS EVENING. CLOUDS AT ROA AND DAN WILL BECOME SCATTERED AS THE DRY SLOT ADVANCES INTO THE REGION. WINDS WILL BE GUSTY TODAY OUT OF THE NORTH TO NORTHWEST. AS THE SURFACE LOW DEEPENS THE WINDS WILL INCREASE...ESPECIALLY EAST OF THE MOUNTAINS. PREV DISCUSSION... (ISSUED 221 AM EST SUN NOV 12 2006) SHORT TERM /TODAY/... DECIDED TO KEEP WIND ADVISORY UP TODAY FOR NORTHWEST MOUNTAINS OF NC NORTHWARD THRU GRAYSON...CARROL AND FLOYD COUNTIES. COLD FRONT CONTINUES ITS MARCH EAST TO THE ATLANTIC THIS MORNING. CLOSED LOW DEVELOPS ACROSS EASTERN VA/NC AND LIFTS TOWARDS NEW ENGLAND TONIGHT. BAND OF SHOWERS AND EMBEDDED THUNDERSTORMS MOVING ACROSS EASTERN THIRD THIS MORNING. WRAP AROUND LOW MOISTURE WILL CLIP THE FAR EAST TODAY AND EXPECT UPSLOPE CLOUDS IN THE WEST. MOST OF PCPN WILL BE LIQUID BUT SOME LIGHT SNOW IS POSSIBLE IN THE HIGHEST ELEVATION. NOT AS IMPRESSED WITH LIMITED MOISTURE AND MORE NORTHERLY WIND COMPONENT. PLAYED TEMPERATURES CLOSE TO MAV GUID. LONG TERM /TONIGHT THROUGH SATURDAY/... CLOSED LOW MOVES OFF THE COAST THEN TOWARD NEW ENGLAND TONIGHT AND MONDAY. WINDS WILL REMAIN STRONG AROUND THE LOW THIS EVENING...THEN START TO DIMINISH AS THE LOW MOVES FURTHER OFFSHORE TONIGHT. SURFACE WINDS WILL BE MUCH LIGHTER BY MONDAY AFTERNOON WITH HIGH PRESSURE APPROACHING AREA. THE Q-VECTOR FORCING AND DEFORMATION AREA STAY JUST EAST OF THE COUNTY WARNING AREA TONIGHT. HOWEVER CLOUDS WILL HOLD IN ACROSS THE EASTERN COUNTY WARNING AREA THROUGH MONDAY AFTERNOON. WENT WARMER THAN MET GUIDANCE ON MONDAY WHICH KEEPS THE PIEDMONT CLOUDY ALL DAY AND COOLER THAN MAV GUIDANCE WHICH HAS MORE SUN IN THE MORNING. COLD AIR IS VERY SHALLOW AND WARM AIR ADVECTION MODERATES THE AIRMASS WITH 850 MB TEMPERATURES WELL AABOVE ZERO BY MONDAY MORNING. SINCE LOW LEVEL WINDS ARE FROM THE NORTH THE UPSLOPE COMPONENT IS NOT THAT GOOD AND WITH SUCH SHALLOW MOISTURE AND COLD AIR AND VERY LIGHT QPF AMOUNTS WILL KEEP JUST LIGHT ANOUMTS OF RAIN AND SNOW IN SOUTHEAST WEST VIRIGINA THROUGH EARLY MONDAY. THE NEXT DEEP TROF DIGGING INTO THE MISSISSIPPI VALLEY ON TUESDAY AND WEDNESDAY WILL BEGIN TO BACK THE LOW LEVELS WINDS. THE LOW LEVEL SOUTHWEST FLOW ON TUESDAY WILL RESULT IN ABOVE NORMAL HIGH TEMPERATURES. MID AND HIGH LEVEL RELATIVE HUMIDITY AND CLOUDS MOVE INTO THE AREA AHEAD OF THIS SYSTEM ON TUESDAY NIGHT. BY WEDNESDAY NIGHT A STRONG LOW LEVEL JET OUT OF THE SOUTHEAST WILL BRING ABUNDANT MOISTURE OFF THE ATLANTIC. THE GOOD DYNAMICS AND UPPER DIFFLUENCE WEDNESDAY NIGHT STILL SUPPORT RAIN SO NO CHANGE NEEDED TO THE FORECAST..EXCEPT WILL INCREASE WINDS SPEEDS A BIT. AVIATION... COLD FRONT WILL EXIT CWA EARLY THIS MORNING. IN WAKE OF FRONT... WINDS WILL BECOME INCREASINGLY GUSTY THIS MORNING WITH SECONDARY PUSH OF WIND ALOFT GIVEN COLD ADVECTION. UPSLOPE FLOW COMBINED WITH LOW LEVEL MOISTURE AND COLD AIR MAY CREATE LOW CLOUDS AND SOME SNOW SHOWERS IN THE NORTHWEST WESTERN AREAS. LOW CLOUD DECK (MVFR/IFR) IN THE WEST WILL BE SLOW TO IMPROVE TODAY...WHILE IN THE EAST DOWNSLOPE FLOW SHOULD ALLOW FOR SOME BREAKS BY LATE MORNING. MVFR/IFR SHOWERS ARE POSSIBLE IN THE FAR EAST TODAY WITH WRAPAROUND PRECIP BAND AS UPPER LOW CLOSES OFF NEARBY. GUSTY AFTERNOON WINDS ARE POSSIBLE ...WITH POTENTIAL FOR GUSTS IN EXCESS OF 40KTS ACRS THE HIGHER ELEVATIONS. WINDS WILL DIMINISH TONIGHT WITH VFR CONDITIONS PREVAILING. MOUNTAIN OBSCURATIONS ARE POSSIBLE TODAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND ADVISORY FOR VAZ015>017 UNTIL 7 PM SUNDAY. NC...WIND ADVISORY FOR NCZ001-002-018 UNTIL 7 PM SUNDAY. WV...NONE. && $$ JH va AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BLACKSBURG VA 950 AM EST SUN NOV 12 2006 .SHORT TERM /REST OF TODAY/... LOW PRES ALONG THE FRONT CONTINUES TO DRIFT SLOWLY NE THRU EASTERN NC THIS MORNING WITH ONGOING NEGATIVE TILT PULLING LIGHT/MOD RAIN BACK ACROSS MUCH OF THE PIEDMONT ATTM. EXPECT AS THE SYSTEM WORKS NE THIS AFTERNOON WILL SEE DRY AIR SLOWLY CUTOFF -RA ON THE SW SIDE AS MID LEVEL AXIS OF CONVERGENCE PIVOTS MORE INTO THE NERN ZONES WHERE WILL KEEP CAT/LIKELY POPS GOING. ELSW ABRUPT DROPOFF IN RH LIKELY ALONG THE SOUTHERN BLUE RIDGE PER NW DOWNSLOPE/SUBSIDENCE BEFORE GETTING BACK INTO MORE UPSLOPISH MOISTURE WESTERN SLOPES. HOWEVER GIVEN FLOW ALOFT MORE NORTHERLY AND BEST MOISTURE OUT WITH COASTAL LOW APPEARS EVEN UPSLOPE MIX OF PRECIP LIKELY VERY LIGHT/SPOTTY THIS AFTERNOON. THIS SEEN IN MOST MODEL OUTPUT ESPCLY LATEST WRF/NMM AND RUC WHICH HAVE VERY LIMITED COVERAGE. THUS PLAN TO CUT POPS TO CHANCE WESTERN SLOPES AND GO WITH LITTLE OR NO PRECIP FROM THE NEW RIVER VALLEY SOUTH. WINDS HAVE BEEN BELOW ADVISORY LEVELS SO FAR WITH WAVE SLOW TO MOVE NE/DEEPEN AND RATHER WEAK 85H JET. EXPECT ONCE ITS GETS A BIT FARTHER EAST AND MIXING INCREASES WILL SEE RIDGES PICK UP ALTHO FORECAST PRES RISES NOT ALL THAT GREAT FOR THE AFTERNOON. OTRW SOME SMALL ADJUSTS TO TEMPS SINCE APPEARS ONLY SLIGHT RISES AT BEST MOST AREAS THRU THE AFTERNOON. && .PREV DISCUSSION... (ISSUED 647 AM EST SUN NOV 12 2006) AVIATION... BLF WILL START OUT WITH IFR CONDITIONS THIS MORNING DUE TO STRONG LOW LEVEL WINS PUSHING MOISTURE UP THE MOUNTAINS. CEILINGS WILL IMPROVE GRADULLY WITH CEILINGS AT BLF BECOMING MVFR BY THE END OF THE DAY. LOW PRESSURE DEVELOPING IN NORTH CAROLINA WILL KEEP VFR CLOUDS IN OVER LYH THROUGH THIS EVENING. CLOUDS AT ROA AND DAN WILL BECOME SCATTERED AS THE DRY SLOT ADVANCES INTO THE REGION. WINDS WILL BE GUSTY TODAY OUT OF THE NORTH TO NORTHWEST. AS THE SURFACE LOW DEEPENS THE WINDS WILL INCREASE...ESPECIALLY EAST OF THE MOUNTAINS. PREV DISCUSSION... (ISSUED 221 AM EST SUN NOV 12 2006) SHORT TERM /TODAY/... DECIDED TO KEEP WIND ADVISORY UP TODAY FOR NORTHWEST MOUNTAINS OF NC NORTHWARD THRU GRAYSON...CARROL AND FLOYD COUNTIES. COLD FRONT CONTINUES ITS MARCH EAST TO THE ATLANTIC THIS MORNING. CLOSED LOW DEVELOPS ACROSS EASTERN VA/NC AND LIFTS TOWARDS NEW ENGLAND TONIGHT. BAND OF SHOWERS AND EMBEDDED THUNDERSTORMS MOVING ACROSS EASTERN THIRD THIS MORNING. WRAP AROUND LOW MOISTURE WILL CLIP THE FAR EAST TODAY AND EXPECT UPSLOPE CLOUDS IN THE WEST. MOST OF PCPN WILL BE LIQUID BUT SOME LIGHT SNOW IS POSSIBLE IN THE HIGHEST ELEVATION. NOT AS IMPRESSED WITH LIMITED MOISTURE AND MORE NORTHERLY WIND COMPONENT. PLAYED TEMPERATURES CLOSE TO MAV GUID. LONG TERM /TONIGHT THROUGH SATURDAY/... CLOSED LOW MOVES OFF THE COAST THEN TOWARD NEW ENGLAND TONIGHT AND MONDAY. WINDS WILL REMAIN STRONG AROUND THE LOW THIS EVENING...THEN START TO DIMINISH AS THE LOW MOVES FURTHER OFFSHORE TONIGHT. SURFACE WINDS WILL BE MUCH LIGHTER BY MONDAY AFTERNOON WITH HIGH PRESSURE APPROACHING AREA. THE Q-VECTOR FORCING AND DEFORMATION AREA STAY JUST EAST OF THE COUNTY WARNING AREA TONIGHT. HOWEVER CLOUDS WILL HOLD IN ACROSS THE EASTERN COUNTY WARNING AREA THROUGH MONDAY AFTERNOON. WENT WARMER THAN MET GUIDANCE ON MONDAY WHICH KEEPS THE PIEDMONT CLOUDY ALL DAY AND COOLER THAN MAV GUIDANCE WHICH HAS MORE SUN IN THE MORNING. COLD AIR IS VERY SHALLOW AND WARM AIR ADVECTION MODERATES THE AIRMASS WITH 850 MB TEMPERATURES WELL AABOVE ZERO BY MONDAY MORNING. SINCE LOW LEVEL WINDS ARE FROM THE NORTH THE UPSLOPE COMPONENT IS NOT THAT GOOD AND WITH SUCH SHALLOW MOISTURE AND COLD AIR AND VERY LIGHT QPF AMOUNTS WILL KEEP JUST LIGHT ANOUMTS OF RAIN AND SNOW IN SOUTHEAST WEST VIRIGINA THROUGH EARLY MONDAY. THE NEXT DEEP TROF DIGGING INTO THE MISSISSIPPI VALLEY ON TUESDAY AND WEDNESDAY WILL BEGIN TO BACK THE LOW LEVELS WINDS. THE LOW LEVEL SOUTHWEST FLOW ON TUESDAY WILL RESULT IN ABOVE NORMAL HIGH TEMPERATURES. MID AND HIGH LEVEL RELATIVE HUMIDITY AND CLOUDS MOVE INTO THE AREA AHEAD OF THIS SYSTEM ON TUESDAY NIGHT. BY WEDNESDAY NIGHT A STRONG LOW LEVEL JET OUT OF THE SOUTHEAST WILL BRING ABUNDANT MOISTURE OFF THE ATLANTIC. THE GOOD DYNAMICS AND UPPER DIFFLUENCE WEDNESDAY NIGHT STILL SUPPORT RAIN SO NO CHANGE NEEDED TO THE FORECAST..EXCEPT WILL INCREASE WINDS SPEEDS A BIT. AVIATION... COLD FRONT WILL EXIT CWA EARLY THIS MORNING. IN WAKE OF FRONT... WINDS WILL BECOME INCREASINGLY GUSTY THIS MORNING WITH SECONDARY PUSH OF WIND ALOFT GIVEN COLD ADVECTION. UPSLOPE FLOW COMBINED WITH LOW LEVEL MOISTURE AND COLD AIR MAY CREATE LOW CLOUDS AND SOME SNOW SHOWERS IN THE NORTHWEST WESTERN AREAS. LOW CLOUD DECK (MVFR/IFR) IN THE WEST WILL BE SLOW TO IMPROVE TODAY...WHILE IN THE EAST DOWNSLOPE FLOW SHOULD ALLOW FOR SOME BREAKS BY LATE MORNING. MVFR/IFR SHOWERS ARE POSSIBLE IN THE FAR EAST TODAY WITH WRAPAROUND PRECIP BAND AS UPPER LOW CLOSES OFF NEARBY. GUSTY AFTERNOON WINDS ARE POSSIBLE ...WITH POTENTIAL FOR GUSTS IN EXCESS OF 40KTS ACRS THE HIGHER ELEVATIONS. WINDS WILL DIMINISH TONIGHT WITH VFR CONDITIONS PREVAILING. MOUNTAIN OBSCURATIONS ARE POSSIBLE TODAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND ADVISORY FOR VAZ015>017 UNTIL 7 PM SUNDAY. NC...WIND ADVISORY FOR NCZ001-002-018 UNTIL 7 PM SUNDAY. WV...NONE. && $$ JH va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 328 PM CST SUN NOV 12 2006 .DISCUSSION...FCST FOCUS IS ON PCPN CHCS WITH APPCH TROF TNT INTO MONDAY AND THEN HANDLING OF SYS FOR MID WEEK. IN THE SHORT TERM...VISIBLE SATELLITE IMAGERY SHOWED APPROACHING MID/HI CLOUDS AHEAD OF 500 MB WAVE THAT RUC ANALYSIS PLACED IN THE WRN DAKOTAS AT 20Z. SERLY SFC WINDS AS RIDGE OF HI PRES SHIFTED EAST BROUGHT REMNANTS OF PERSISTENT LAKE EFFECT CLOUDS ONSHORE...KEEPING LOCATIONS NEAR LAKE MI IN AND OUT OF CLOUDS. WILL MONITOR LATEST TRENDS FOR ERLY EVENING CLOUD FCST. COMPETING FACTORS MAKE PCPN CHANCES FOR CWA LATE TONIGHT/MONDAY MORNING DIFFICULT TO PIN DOWN. BEST ISENTROPIC LIFT ON BOTH NAM AND GFS 290-300K SFCS CROSSES CWA BETWEEN 00Z AND 06Z WITH 30-35 KT LLJ...BUT MOISTURE LAGGING. COND PRESSURE DEFICITS OF 100-200 MB WITH BEST LIFT...THO GFS HAS AN ANOMALOUS SECONDARY BULLSEYE OF NET ADIABATIC ISENTROPIC OMEGA AT 12Z OVER S CNTRL WI ON LEADING EDGE OF LOWERING PRES DEFICIT GRADIENT. GOES SOUNDER IMAGERY CONFIRMS DRY AIR IN PLACE OVER RGN...19Z RUC PWATS OF 0.25 INCH OR LESS OVER SRN WI...WITH RETURN FLOW JUST NOW LIFTING NWD ALONG SFC TROF AHEAD OF DEVELOPING SFC LOW IN PANHANDLE REGION. 850 MB DEW POINT FCSTS INDICATE NARROW RIBBON OF HIER DEW POINTS ARE COINCIDENT WITH 850 MB TROF AXIS...BUT BEHIND BEST ISENTROPIC LIFT. CROSS SECTIONS SHOW STRONG MID LVL FRONTOGENETIC FORCING OVER CWA BETWEEN 12Z AND 18Z...BUT BETTER OMEGA ALOFT IS OFFSET BY DOWNWARD AGEOSTROPHIC FLOW BELOW 800MB...PROBABLY FROM CAA AT 850 MB AND BELOW THAT BEGINS AROUND 06Z MON...WITH WEAK 1000-850 MB FRONTOGENESIS TO OUR WEST AT 00Z MON DIMINISHING WITH TIME AFTER 06Z TO NEAR NOTHING BY 12Z. NARROW THETA E RIDGE TO PUSH ALONG/AHEAD OF TROF AS IT CROSSES CWA MONDAY MORNING. WILL TIE WHAT SHOULD BE LIGHT/SCT PCPN TO THIS AXIS...WHICH ALSO ALIGNS WELL WITH COLUMN SATURATION ON BUFKIT SNDGS. TOP DOWN AND BOURGOIUN PCPN TYPE METHODS INDICATE ALL RAIN FOR CWA. NEXT CONCERN IS MIDWEEK SYSTEM. SWD TREND NOTED BY PREV FCSTR CONTINUES WITH SUN 18Z NAM RUN TRACKING SFC LOW DVLPG OVR SRN MO AT 06Z WED...THEN MOVG ALONG OHIO RVR VLY TO FAR S CNTRL OHIO BY 06Z THUR. 12Z GFS JUST A TAD FARTHER NORTH WITH LOW TRACK IN SAME TIME PERIOD...THEN LIFTS IT NWD TO NR WRN LAKE ERIE AND RETROGRADES/REDEVELOPS NR SAGINAW BAY AS CLOSED 500 MB LOW DEEPENS. 12Z ECMWF ALSO TRENDING WITH OHIO RVR SOLUTION BY 12Z THUR WITH CLOSED 500 LOW FARTHER SOUTH THAN PREV RUNS. WILL HOLD ON TO CHC POPS FOR WED AS WELL AS RAIN OR SNOW FOR TYPE WITH BETTER CLARITY EXPECTED FOR TRACK/TIMING IN LATER RUNS. && .MKX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ REM wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 310 PM CST SUN NOV 12 2006 .SHORT TERM...THROUGH WEDNESDAY NIGHT PRIMARY FORECAST CONCERNS WERE WITH PRECIPITATION CHANCE/TYPE TONIGHT INTO EARLY MONDAY AND AGAIN TUESDAY INTO WEDNESDAY NIGHT. INFRARED AND VISIBLE SATELLITE IMAGERY INDICATED CONSIDERABLE MID AND HIGH LEVEL CLOUDS ADVANCING ACROSS THE UPPER MISSISSIPPI VALLEY. THIS WAS IN ADVANCE OF SURFACE COLD FRONT...WHICH EXTENDED ACROSS EASTERN DAKOTAS AND NEBRASKA INTO CENTRAL KANSAS. NARROW BAND OF PRECIPITATION NOTED ON REGIONAL RADAR FROM NORTHEAST TO WEST CENTRAL MN. LATEST RUC SUPPORTS THIS PRECIPITATION AS ASSOCIATED WITH 700-500MB FRONTOGENESIS. WATER VAPOR IMAGERY INDICATED MID LEVEL TROUGH EXTENDING NORTH-SOUTH ACROSS NATIONS MIDSECTION...WITH VIGOROUS WAVE IN THE TEXAS PANHANDLE AREA. 12Z 12NOV06 MODEL SOLUTIONS HAD EXCELLENT CLUSTERING WITH RESPECT TO UPPER LEVEL SURFACE FEATURES AFFECTING THE FORECAST AREA TONIGHT INTO EARLY MONDAY. THEREFORE...FORECAST CONFIDENCE WAS HIGH THAT WE WILL RECEIVE A LIGHT PRECIPITATION EVENT. IN FACT...80-100 PERCENT OF GFS ENSEMBLES SUPPORTED PRECIPITATION DURING THE OVERNIGHT HOURS. IN ADDITION...NCEP SREF ENSEMBLE SUPPORTED HIGHER PROBABILITY OF SNOW IN NORTHERN PART OF THE FORECAST AREA...WITH BETTER PROBABILITY OF RAIN ELSEWHERE. ANOTHER AND MORE VIGOROUS SYSTEM SHOULD IMPACT PARTS OF THE MIDWEST AT MIDWEEK. EVEN THOUGH MODEL DETAILS STILL DIFFER A BIT...THE CONSENSUS APPEARS TO BE INCREASING TOWARD A SOLUTION OF A CLOSED 500MB LOW DEVELOPING OVER THE MID MISSISSIPPI AND LOWER OHIO VALLEY BY WEDNESDAY. THIS SHOULD EFFECTIVELY KEEP THE HEAVIEST QPF SOUTH OF OUR FORECAST AREA....WHICH AGREED WITH NCEP SREF ENSEMBLE MEMBERS. THEREFORE...CONFIDENCE WAS INCREASING IN THIS AS A PROBABLE SOLUTION...WHICH CURRENT DATA BASE ALREADY SUPPORTS. TONIGHT INTO EARLY MONDAY...MODELS CONTINUED TO INDICATE A CONSISTENT SIGNAL WITH REGARD TO FRONTOGENETIC FORCING ASSOCIATED WITH UPPER LEVEL WAVE. NORTH-SOUTH CROSS SECTION INDICATED A NARROW BUT STRONG UPWARD VERTICAL MOTION SIGNAL SLIDES ACROSS THE FORECAST AREA. THIS SUGGESTS PRECIPITATION MAY FALL STEADILY FOR AWHILE...ALTHOUGH TRANSITORY NATURE OF THE FORCING SHOULD PRECLUDE HEAVY AMOUNTS PER MODEL QPF. BECAUSE OF CONSISTENTLY STRONG FORCING SIGNAL... CONFIDENCE WAS HIGH TO INCREASE PRECIPITATION PROBABILITIES INTO CATEGORICAL VALUES. ACCORDING TO NCEP SREF AND BUFKIT PRECIPITATION TYPE ALGORITHMS... PRECIPITATION PROBABILITIES FOR SNOW SHOULD BE BEST ACROSS NORTHERN MOST SECTIONS OF THE FORECAST AREA. THEREFORE...TAILORED SNOW AMOUNTS IN THE DATA BASE ACCORDINGLY...WITH AROUND 2 INCHES OF ACCUMULATION IN NORTH CENTRAL WI AND AN INCH OR LESS ELSEWHERE. TUESDAY INTO WEDNESDAY NIGHT...MORE VIGOROUS SYSTEM SHOULD IMPACT PARTS OF THE MIDWEST...ALTHOUGH BEST DYNAMICS APPEAR TO RESIDE SOUTH OF THE FORECAST AREA WHERE 500MB LOW CLOSES OFF. DIFFERENCES IN STRENGTH OF FORCING NOTED BETWEEN NAM/WRF AND GFS...WITH GFS STRONGER WITH REGARD TO DEEP LAYERED Q-G CONVERGENCE. IN ADDITION... SREF AND BUFKIT PRECIPITATION TYPE ALGORITHMS SUGGEST COULD BE RAIN AND/OR SNOW. ONLY CHANGE TO DATA BASE IN THIS TIME FRAME WAS TO TRIM EASTWARD EXTENT OF PRECIPITATION PROBABILITIES INTO CENTRAL WI ON TUESDAY. .LONG TERM...THURSDAY THROUGH SUNDAY THURSDAY INTO FRIDAY...OPERATIONAL ECMWF AND GFS HAVE COME INTO BETTER CONSENSUS ON CLOSED 500MB LOW ADVANCING FROM OHIO VALLEY INTO EASTERN GREAT LAKES AND SOUTHEAST CANADA. THIS WAS CORROBORATED BY MREF ENSEMBLES. THUS...FORECAST CONFIDENCE INCREASING IN DETAILS WITHIN CURRENT DATA BASE...WHICH SUPPORTS DRY CONDITIONS. SATURDAY INTO SUNDAY...ECMWF AND GFS HAD SIGNIFICANT DIFFERENCES IN THE DETAILS OF UPPER LEVEL AND SURFACE FEATURES. MREF ENSEMBLES SUPPORTED A LESS AMPLIFIED FLOW...THEREFORE FORECAST CONFIDENCE WAS LOW IN THIS TIME FRAME. NO CHANGES WERE MADE IN THE EXTENDED OUTLOOK AND THUS MAINTAINED DRY FORECAST. && .ARX WATCHES/WARNINGS/ADVISORIES... MN...NONE. IA...NONE. WI...NONE. && $$ THOMPSON wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1200 AM EST MON NOV 13 2006 .AVIATION... THE LATEST IR SATELLITE LOOP SHOWS MVFR STRATUS DECK CONTINUING TO SPREAD NORTH AND WEST ACROSS SOUTHERN LOWER MI AND NORTHERN IN. GIVEN THE LARGE EXPANSE OF THESE CLOUDS AND BASED ON THE 00Z MODEL SOUNDINGS...WILL EXTEND THE MVFR CLOUDS IN THE TAFS THROUGH THE ENTIRE MORNING. SOUTHERLY FLOW IN ADVANCE OF A FRONTAL BOUNDARY THIS AFTERNOON WILL ALLOW THE LOW CLOUDS TO SCATTER OUT BY 18Z. LIMITED MOISTURE FROM 3K TO 8K FEET SHOULD PREVENT MUCH IN THE WAY OF PRECIP WITH THE NEXT FRONT. && .PREV DISCUSSION...ISSUED 843 PM EST SUN NOV 12 2006 UPDATE... THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 900MB. MODEL SOLUTIONS ARE ALL TOO DRY BELOW THIS INVERSION LEVEL BASED ON THE DTX SOUNDING. IT IS NO SURPRISE THEN THAT THE STRATUS DECK HAS NOT DIMINISHED MUCH SINCE SUNSET. WITH THE FLOW NEAR THE CLOUD BASE FORECAST BY BOTH RUC AND NAM12 TO BECOME MORE SOUTHEASTERLY THROUGH 06Z...EXPECT THE STRATUS THAT IS NOW COVERING THE EASTERN THIRD OF THE FORECAST AREA TO BUILD BACK TO THE WEST. THE IR SATELLITE LOOP OVER THE LAST HOUR HAS ALREADY SHOWED THE STRATUS ADVANCING NORTHWEST ACROSS THE DETROIT METRO AREA. THE LOW LEVEL FLOW IS STILL FORECAST TO BECOME MORE SOUTH-SOUTHWESTERLY BETWEEN 09Z AND 12Z...WHICH MAY ALLOW SOME BREAKS TO DEVELOP ACROSS THE WESTERN PORTION OF THE FORECAST AREA TOWARD DAYBREAK. WILL UPDATE THE FORECAST TO REFLECT CURRENT CLOUD TRENDS. ALTHOUGH TEMPS IN LOCATIONS THAT EXPERIENCED PROLONGED CLEAR SKIES THIS EVENING HAVE DROPPED TO NEAR 30...WILL INCREASE TEMPS IN THE OVERNIGHT PERIOD TO REFLECT THE INCREASE IN CLOUD COVER. PREV DISCUSSION...ISSUED 352 PM EST SUN NOV 12 2006 SHORT TERM...TONIGHT AND MONDAY NOT A WHOLE LOT TO TALK ABOUT IN THE SHORT TERM. SLOW EROSION OF STRATOCU TO CONTINUE THIS EVENING. THIS WILL SET UP A MOSTLY CLEAR NIGHT AS RIDGING HOLDS ON OVER LOWER MICHIGAN. DESPITE WARMER AIRMASS TONIGHT...GOOD RADIATIONAL COOLING CONDITIONS (CLEAR AND CALM) WILL ALLOW SURFACE TEMPERATURES TO DROP SEVERAL DEGREES LOWER THAN LAST NIGHT. LOWS IN THE UPPER 20'S WILL BE COMMONPLACE...WITH A FEW LOCATIONS DIPPING INTO THE MID 20'S. HIGH CLOUDS WILL SLIDE IN ON MONDAY IN ADVANCE OF NEXT SHORTWAVE APPROACHING FROM THE WEST. DRY AIR IN PLACE WILL BE TOO STRONG TO SUPPORT ANY PRECIP AHEAD OF THIS WAVE...AND LACK OF IDENTIFIABLE SURFACE FEATURE WILL KEEP LIFT VERY MINIMAL. PLENTY OF SUNSHINE AND WEAK RETURN FLOW SHOULD LEAD TO TEMPERATURES RIGHT AROUND NORMALS...IN THE UPPER 40S. LONG TERM...MONDAY NIGHT THROUGH SUNDAY LARGE STORM STILL SET FOR MID/LATE THIS WEEK AND ONLY HAVE TO ADJUST TIMING SLIGHTLY IN THIS FORECAST PACKAGE. MODEL CONSENSUS IS SLIGHTLY SLOWER IN LIFTING THE LEAD SURGE OF MOISTURE INTO THE AREA. INSTEAD OF WEDNESDAY MORNING...THIS MOISTURE IS NOW FORECAST TO LIFT THROUGH THE REGION ON WEDNESDAY EVENING. WILL BACK OFF ON WORDING SLIGHTLY AND FOCUS THE BEST CHANCE OF RAINFALL ON WEDNESDAY NIGHT & THURSDAY. GIVEN THE CONTINUED CONTINUITY OF THE MODELS...WILL ALSO INCREASE THE CHANCE OF PRECIPITATION TO 60% OR BETTER DURING THIS TIMEFRAME. THE TRACK/STRENGTH OF THIS SYSTEM STILL LEADS TO A LARGE INGESTION OF MILD/MOIST ATLANTIC AIR IN SOUTHEAST FLOW. THIS WILL MAKE THE MAIN EVENT MAINLY RAIN THROUGH THURSDAY...BEFORE THE COLD AIR IN THE CORE OF THE UPPER LOW LIFTS NORTH/NORTHEAST INTO THE REGION AND ALLOWS A GRADUAL TRANSITION TO RAIN/SNOW MIX AND PERHAPS ALL LIGHT SNOW BY LATE THURSDAY NIGHT OR FRIDAY...ALLOW MOST OF THE MOISTURE AND LIFT WILL BE NORTH OF THE AREA BY THEN. WILL MAINTAIN THE CURRENT TEMPERATURE FORECAST BASICALLY INTACT. GENERALLY COOL WEATHER CAN BE EXPECTED...WITH THE MILDEST PERIOD AROUND WEDNESDAY AS THIS SYSTEM APPROACHES...AND TEMPERATURES CLIMB TO NEAR 50 DURING THE DAY. THEREAFTER...A COOLING TREND CAN BE EXPECTED INTO NEXT WEEKEND...ALTHOUGH NOT TOO BAD FOR THIS TIME OF THE YEAR AS HIGHS WILL STILL CLIMB TO 40 OR BETTER. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...SHULER LONG TERM....DG AVIATION/UPDATE...CONSIDINE YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 303 AM CST MON NOV 13 2006 .DISCUSSION... PRECIPITATION ASSOCIATED WITH MID LEVEL SHORTWAVE/FRONTOGENESIS CONTINUES TO SHIFT EAST ACROSS THE FA THIS MORNING. THE RUC/NAM/GFS MODELS ALL FORECAST THIS AREA TO EXIT THE EASTERN CWA BY MID MORNING...SO POPS HAVE BEEN ALIGNED ACCORDINGLY...WITH 20-30 POPS ENDING ACROSS THE WI COUNTIES BY 15Z. HAVE MAINTAINED COLDER HIGH TEMPERATURES ACROSS THE SOUTH/EAST TODAY...TAKING INTO CONSIDERATION THE LINGERING CLOUD COVER AND SNOWPACK. MOSTLY CLEAR SKIES ACROSS THE WEST SHOULD YIELD RELATIVELY WARMER READINGS IN THE MID/UPPER 40S. THE PATTERN WILL REMAIN ACTIVE AS A BROAD TROUGH BECOMES ESTABLISHED ACROSS THE CONUS DURING THE BEGINNING OF THE WEEK. NAM/GFS MODELS CONTINUE TO TREND SOUTHWARD WITH THE PLACEMENT OF A SHORTWAVE /AND EVENTUAL CLOSED LOW/ THAT DEEPENS EAST OF THE CENTRAL ROCKIES. MEANWHILE...THE PARENT LOW IS PROGGED TO PASS ACROSS SOUTHERN MANITOBA/SASKATCHEWAN. ASSOCIATED WEAK INVERTED TROUGH SLIDES ACROSS THE FORECAST AREA BETWEEN TUESDAY AFTERNOON AND WEDNESDAY MORNING. HAVE ORIENTED HIGHER CHANCE POPS WITH THE TROUGH...BUT HAVE SCALED BACK SLIGHTLY DUE TO SOUTHWARD TRENDS OF THE MAIN SYSTEM. EXPECT TEMPERATURES TO RETREAT BACK BELOW NORMAL ON WEDNESDAY/WEDNESDAY NIGHT. DRY WEATHER IS EXPECTED FOR THURSDAY AS WEAK MID LEVEL RIDGING BUILDS ACROSS THE CENTRAL UNITED STATES. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...SNOW ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR BARRON- CHIPPEWA-DUNN-EAU CLAIRE-RUSK COUNTY(IES). && $$ LS mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 225 AM CST MON NOV 13 2006 .DISCUSSION... N-S BAND OF RAIN OR SHOWERS MOVG EWD THRU THE CWA EARLY THIS MRNG AHD OF SHRTWV TROF ACRS THE NRN PLAINS AND ASSOCIATED WK CDFNT/SFC TROF EXTDG FM ERN MN S-SW THRU ERN OK. LATEST RUC ANLYS DEPICTS RELATIVELY STG 800-600 MB WAA EXTDG FM SERN IA S-SW THRU N CNTRL AR AHD OF LOW LVL TROF. BOTH NAM AND GFS MDLS ALSO SHOW UPR LVL DIVERGENCE ACRS MUCH OF THE CWA THIS MRNG AHD OF UPR LVL TROF. IT APRS THAT MOST OF THIS PCPN SHOULD PUSH E OF THE CWA BY THIS AFTN AS THE MID-UPR LVL TROF MOVES E OF THE AREA. THERE SHOULD BE AT LEAST PARTIAL CLRG OVR THE WRN PTN OF THE CWA THIS AFTN...BUT LOOKING AT MDL RH PROGS LOW LVL CLOUDINESS MAY LINGER OVR THE ERN PTN OF THE CWA THIS AFTN AND POSSIBLY INTO TGT. WK SHRTWVS MOVG FAIRLY RAPIDLY EWD THRU THE REGION MAY ALSO BRING SOME MID-UPR LVL CLOUDINESS TGT OVR THE CWA. MAX TEMPS SHOULD BE SLIGHTLY WRMR ON TUE WITH S-SWLY LOW LVL WNDS OVR THE CWA AHD OF DVLPG LOW PRESSURE SYSTEM IN THE LEE OF THE ROCKIES. CLOUD CVR WILL BE INCRSG BY TUE AFTN BUT PCPN SHOULD HOLD OFF TIL TUE NGT. RAIN/SHRA WILL SPREAD EWD THRU MOST OF THE CWA TUE NGT AHD OF DPNG MID-UPR LVL TROF MOVG EWD THRU THE PLAINS STATES. BOTH NAM AND GFS MDLS DVLP MID LVL CUTOFF LOW BY 12Z WED...ALTHOUGH THEY HAVE DIFFERING POSITIONS OF MID LVL LOW AND ASSOCIATED SFC LOW. GFS MDL IS FURTHER S WITH MID LVL LOW AND ASSOCIATED SFC LOW ON WED MOVG IT THRU NRN AR...WHILE THE NAM MDL HAS IT MOVG EWD THRU SRN MO. ALTHOUGH EITHER SOLUTION WOULD BRING PCPN TO MUCH OF THE CWA TUE NGT AND WED...THE GFS SOLUTION WOULD HAVE THE HIGHEST QPF A LTL FURTHER S AND HAVE SLIGHTLY COOLER TEMPERTURES FOR THE CWA. WILL GO WITH A COMPROMISE SOLUTION FOR NOW AS THERE IS STILL PLENTY OF UNCERTAINTY WITH THE TRACK OF THE MID LVL AND SFC LOW. WILL INCLUDE RELATIVELY HI POPS FOR TUE NGT AND WED ESPECIALLY OVR THE SRN HALF OF THE CWA. BOTH MDLS INDICATE INCRSG UPR LVL DIVERGENCE OVR THE CWA TUE NGT WITH APPROACH OF UPR LVL TROF AND IN LEFT EXIT REGION OF ULJ STREAK ACRS THE SRN PLAINS. LOOKING AT MID LVL Q CNVG...MID LVL MOISTURE AND 700 MB CVNG WILL LIKELY HAVE DEFORMATION TYPE PCPN ON WED INTO WED EVNG ACRS CNTRL AND SRN PTNS OF THE CWA JUST N OF THE TRACK OF THE DEEP MID LVL CLOSED LOW. GKS && .AVIATION... FOR THE 06Z TAFS...RWS AND ISOLATED TRWS HAVE DEVELOPED AHEAD OF COLDFRONT THAT IS JUST ENTERING MO AS OF 05Z. STILL HAVE VFR CIGS AND VSBYS...WHICH WILL PREVAIL AREAWIDE THROUGHOUT MOST OF THE FORECAST PERIOD. ATMOSPHERE REMAINS QUITE DRY BELOW H700...WITH SFC DEWPTS STILL IN THE UPPER 20S AND 30S...EVEN WHERE SOME LIGHT RAIN HAS FALLEN. STILL FEEL THAT LO LEVELS WILL MOISTEN UP SOME WITH LIGHT RAIN SHOWERS POSSIBLE FROM ABOUT 07Z TIL 13Z FROM W TO E WITH MAIN FORCING COMING FROM SHORTWAVE ITSELF. MVFR CIGS ARE EXPECTED MONDAY MORNING...BUT WENT IN THE UPPER RANGE...AROUND 3K FT FOR ALL TAF SITES. BEGIN TO BREAK UP CIGS A LITTLE FOR KUIN AND KCOU AROUND 22Z AND FOR KSUS AND KSTL AROUND 01Z. BYRD && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX mo AREA FORECAST DISCUSSION...UPDATED TO ADD 3RD PARAGRAPH NATIONAL WEATHER SERVICE WILMINGTON OH 301 AM EST MON NOV 13 2006 .SHORT TERM /REST OF TODAY THROUGH WEDNESDAY/... SURFACE ANALYSIS SHOWS HIGH PRESSURE RIDGE FROM GREAT LAKES INTO THE TENNESSEE VALLEY. SATELLITE IMAGERY SHOWS STRATUS HOLDING TIGHT OVER FORECAST AREA CIRRUS MOVING IN FROM THE WEST. GFS AND NAM ARE IN PRETTY GOOD AGREEMENT THROUGH THE FORECAST PERIOD. WEAK SURFACE HIGH WILL DOMINATE WEATHER THROUGH TUESDAY NIGHT. A DIGGING UPPER TROF WILL QUICKLY DEEPEN A SURFACE LOW AND MOVE IT INTO THE OHIO VALLEY ON WEDNESDAY. THIS WILL BRING PLENTY OF SHOWERS BEGINNING WEDNESDAY AND LASTING INTO THRU FRIDAY NIGHT. GFS 1000-850 THICKNESSES SUGGEST A MIX OF SNOW OR ALL SNOW BY FRIDAY NIGHT. AS FOR TODAYS CLOUD FORECAST IT IS NOT STRAIGHT FORWARD. STRATUS IS STILL HANGING TIGHT WITH HIGH LEVEL CLOUDS WORKING IN FROM THE WEST. NAM/RUC SHOWING RH DECREASING TO SOME DEGREE TODAY. THINK THERE WILL BE SOME MIXING OUT...BUT HIGH LEVEL CLOUDS WILL DETER THAT TO SOME DEGREE ESPECIALLY THIS TIME OF YEAR. THUS WILL GO WITH BECOMING PARTLY CLOUDY/SUNNY FOR THIS AFTERNOON...HOWEVER CONFIDENCE IS NOT REAL HIGH. WILL REMOVE THE MENTION OF THUNDER FOR WEDNESDAY. BOTH THE NAM AND GFS SHOW NO ELEVATED OR SURFACE BASED INSTABILITY. MAV TEMPS LOOK REASONABLE. THE ONLY CHANGES WERE MADE IN THE FIRST AND FIFTH PERIODS WERE MAV WAS LOWERED SEVERAL DEGREES. TIPTON && .PREV DISCUSSION... /ISSUED 1233 AM EST MON NOV 13 2006/ AVIATION /12Z-12Z/... SC DECK REMAINS ENTRENCHED BENEATH BNDRY LYR INVERSION ATTM. HAVE ACTUALLY SEEN AN EXPANSION WESTWARD INTO EASTERN INDIANA WITH LO LVL ERLY FLO HAVING DVLPD. EVEN WITH UPR RIDGE AXIS OVER REGION CURRENTLY DO NOT SEE ANY REASON TO NOT KEEP MVFR SC DECK AT ALL TAF SITES THRU THE REMAINDER OF THE NIGHT. NAM INDCG LO LVL FLO WILL VEER TO SRLY BY DAYBREAK...AND AM STILL THINKING THAT LO LVL WAA SHOULD HELP TO PROMOTE BNDRY LYR MIXING AND BREAK UP SC DECK ACRS WESTERN OHIO DURING MRNG HOURS. MID/HI LVL CLOUDS ACRS MID MISSISSIPPI VLY IN ASSOC WITH S/WV WHICH WILL APPCH REGION BY TONIGHT. AS SC BREAKS...AC/CI WILL STREAM INTO REGION DURING AFTN HOURS AND LOWER THIS EVNG AS S/WV MOVES THRU FCST AREA. RYAN PREV DISCUSSION... /ISSUED 315 PM EST SUN NOV 12 2006/ LONG TERM /WEDNESDAY THROUGH SUNDAY/... LOOKS LIKE MODELS CONTINUE TO SLOW UP SYSTEM FOR MID WEEK WITH ONSET OF PRECIPITATION MAINLY AFTER 06Z WED BUT BETTER CHANCES AFTER 12Z WED. LOW PRESSURE SYSTEM CENTERED OVER WESTERN IL AT AROUND 12Z WED WILL MOVE SLOWLY ESE AS A SECOND LOW DEVELOPS OVER WESTERN SC. THEN THE IL/IN LOW WILL MOV NE ACROSS OH INTO THE GRT LKS BY 18Z THU. THIS COINCIDES WITH THE MOVEMENT OF AN UPPER LEVEL LOW. THE UPPER LEVEL LOW AND SURFACE LOW WILL MOVE WELL NORTH OF THE GRT LKS INTO CANADA FRI THROUGH SUN. THIS WILL KEEP THE REGION IN A NW FLOW WITH THE MINIMAL THREAT FOR RAIN/SNOW SHOWERS THROUGH SUNDAY. BEST CHANCES OF PRECIPITATION WILL BE WED INTO THU NIGHT. A MIX OF RAIN SHOWERS AND SNOW SHOWERS MAY BE SEEN...MAINLY EARLY THU MORNING AND FRIDAY NIGHT. AT THIS TIME...HAVE RESTRICTED MENTION OF SLIGHT CHANCE RAIN/SNOW SHOWERS TO SATURDAY NIGHT IN LATER PERIODS OF EXTENDED. HIGHS START OUT IN THE 50S WED AND LOWS THU IN THE 40S WITH A GENERAL COOLING TREND THROUGH THE REMAINDER OF THE EXTENDED PERIOD. EXPECT HIGHS FOR THE MOST PART IN THE 40S AND LOWS IN THE 30S. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 404 AM CST MON NOV 13 2006 .DISCUSSION...FCST FOCUS ON PCPN TRENDS TODAY AND THEN ON MODEL TENDENCIES FOR MID WEEK SYS. MID LEVEL SHORTWAVE APPCH CWA AND PROGGD TO PASS THRU THIS AFTN. FAIRLY SOLID AREA OF RAIN COMING ACRS CWA LENDS CONFIDENCE TO BOOSTING UP SUBSTANTIALLY FROM GFS MOS. MODEL DERIVED H7 VV ASSOC W/H7 WAVE IS BEST BETWEEN 12Z AND 18Z. SOME COLLAPSE OF H8 TEMPS AND 1000-500 MB THICKNESS BLO 0C AND 540DM THIS MRNG ESP FOR NW PTN CWA...SO MIXY POTENTIAL SEEMS BEST THERE...THO DEW POINTS AOA 32 POOLING NEAR SFC FEATURE MAY KEEP LOWEST LEVELS LESS THAN IDEAL FOR MIXY. NAM SOUNDING IS ONLY ONE TO HINT AT SN IN MSN WHILE RUC AND GFS SHOWS MORE OF A RAIN SOUNDING. BEST INSTABILITY... EPV...NOTED ACRS ERN CWA ERLY THIS MRNG BUT IS ALSO WITHIN DRIER AMS. WRF ARW HAS PRETTY GOOD HANDLE ON QPF TRENDS AND LINGERS SOME INTO THE EARLY AFTN HRS ACRS THE FAR EAST AND MAKES SENSE GIVEN THE SFC/H8 AND MID LEVEL FEATURES HAVE YET TO PASS THEN...SO WILL HAVE POPS HIGHER IN THE EAST THRU MID AFTN. EXTENT OF CLRG BEHIND THIS SYSTEM A CONCERN. NGM AND NAM MOS KEEP US OVC UFN WHILE THE GFS MOS ALSO INDICATES MORE CLOUDS THAN NOT THRU TUE. WILL LEAN MORE TOWARDS THE PESSIMISSTIC SIDE GIVEN LLVL RH PROGS...LINGERING H8 COOL POOL AND LIGHT WIND REGIME IN WAKE OF DEPARTING SYS. ATTM BACK EDGE WELL DEFINED ACRS CNTRL IA INTO SRN MN AND MOVG SWIFTLY EWD...THO MORE LOW CLOUDS ACRS NRN MN APPEAR TO BE HEADING SEWD...SO EXTENT OF CLRG STILL IN QUES. IN FACT SOME CONCERN TNGT FOR FOG POTENTIAL IF WE WERE TO CLEAR OFF. BL WOULD BE PLENTY MOIST FROM LGT PCPN AND SFC THRU H8 WINDS PROGGD TO BE QUITE LGT. WILL BANK ON AT LEAST SOME PARTIAL CLRG IN THE WRN CWA FOR TNGT ADN INTRODUCE PATCHY FOG THERE. NEXT CONCERN SHIFTS TO THE MID WEEK SYSTEM. MODELS CONTINUE TO TREND THE KEY FEATURES FURTHER AWAY FROM THE AREA. STG LOW PROGGD TO DEVELOP IN CENTRAL PLAINS TUE NGT AND THEN SHIFT ENE AND CONTINUE INTO THE OH VLY/ERN GRT LAKES RGN FOR WED AND THU. THIS TRANSLATES TO A GLANCING SHOT QPF WISE. H7 RH GRAZES THE SRN AND ERN CWA THO H8 IS PARCHED. LOOKS LIKE MAIN CONCERN FOR NOW IS WINDS IN ERN CWA AND OVER THE LAKE. TIGHT GRADIENT ARND THIS SYS WILL LIKELY CAUSE SOME RATHER WINDY CONDITIONS...ESP ACRS ERN CWA AND OVER LAKE MICHIGAN. HOWEVER IF MODELS CONTINUE TREND OF TAKING SYS FURTHER EAST THEN IMPACT OF WINDS TO BE DIMINISHED. && .MKX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 10 wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 920 AM EST MON NOV 13 2006 .SYNOPSIS... 14Z WATER VAPOR AND RUC ANALYSIS SHOWING CLOSED UPPER LOW THAT EFFECTED THE MID-ATLANTIC AND SOUTHEASTERN STATES THIS PAST WEEKEND PULLING OFF THE ATLANTIC COAST TO THE SOUTH OF NEW ENGLAND. BEHIND THIS SYSTEM BRIEF UPPER RIDGING HAS MOVED INTO THE SOUTHEASTERN CONUS. FURTHER UPSTREAM A SERIES OF DISTURBANCES ARE SEEN IN THE FLOW...WITH ONE SHARP UPPER TROUGH MOVING THROUGH THE MISSISSIPPI VALLEY...AND ANOTHER WEAKER SYSTEM MOVING INTO THE INTERMOUNTAIN WEST. EVEN FURTHER BACK...ONE MORE PIECE OF ENERGY OFF THE PACIFIC NORTHWEST COAST WILL BE COMING ASHORE THIS EVENING AND OVERNIGHT. THIS ENERGY WILL EVOLVE OVER THE NEXT 72 HOURS INTO A STRONG AND DYNAMIC SYSTEM ACROSS THE LOWER MISSISSIPPI VALLEY AND THEN POSSIBLY BECOME OUR NEXT SIGNIFICANT WEATHER EVENT BY WEDNESDAY AFTERNOON OR EVENING AS THE SYSTEM RAPIDLY PUSHES EAST. AT THE SURFACE WE SEE HIGH PRESSURE CENTERED OFF TO THE NORTH AND WEST OF THE FORECAST AREA. THIS HIGH WILL SLOWLY DRIFT EAST THROUGH THE DAY ON TUESDAY REACHING THE SOUTHEASTERN COAST BY LATER TUESDAY AND TUESDAY NIGHT. THIS HIGH WILL BRING A CONTINUATION OF THE FAIR AND DRY WEATHER THROUGH THE DAY ON TUESDAY. && .UPDATE... 12Z KTLH SOUNDING SHOWING JUST ABOUT AS DRY AN AIRMASS AS WE GET AROUND THESE PARTS. DEWPOINT DEPRESSIONS FROM JUST ABOVE THE SURFACE UP THROUGH 500 MB ARE RUNNING BETWEEN 30-40C WITH 15-20C THROUGH THE REMAINDER OF THE COLUMN ABOVE 500MB. THIS IS RESULTING IN A PW VALUE OF ONLY 0.16" (~18% OF NORMAL). NO SIGNIFICANT UPDATES EXPECTED TO THE FORECAST FOR TODAY AT THIS TIME. STARTED OFF ON THE COOL SIDE THIS MORNING. COLDEST INTERIOR SPOTS FELL TO THE LOWER AND MIDDLE 30S AROUND SUNRISE...WITH COASTAL LOCATIONS REMAINING IN THE LOWER TO MIDDLE 40S. EARLY VISIBLE SATELLITE IMAGES SHOWING MOSTLY CLEAR SKIES THIS MORNING ACROSS THE ENTIRE REGION. SOME HIGHER CIRRUS CAN BE SEEN WELL TO THE WEST ACROSS WESTERN AL/MS...AND SOME OF THIS HIGHER CLOUD MAY BEGIN TO APPEAR FROM THE WEST LATE IN THE DAY. CURRENT FORECAST OF MOSTLY SUNNY SKIES WITH JUST SOME PASSING CIRRUS AT TIMES AND HIGHS WITHIN A FEW DEGREES OF 70 LOOKS ON TRACK FOR THIS AFTERNOON. .MARINE... WINDS REMAIN LIGHT ACROSS THE COASTAL AND OFFSHORE WATERS WITH NORTH TO NORTHEASTERLY FLOW AT 5-10 KNOTS THIS MORNING. OFFSHORE BUOYS ARE RUNNING BETWEEN 1-2 FEET...IN LINE WITH THE CURRENT FORECAST. && .AVIATION... PATCHY BR/HZ INVOF KVLD WILL CAUSE MVFR VSBYS UNTIL MID-MORNING. OTHERWISE...VFR CONDITIONS FCST THROUGH TONIGHT. SOME MID/HIGH CLOUDS AOA FL150 WILL MOVE WEST TO EAST ACROSS THE TERMINALS THIS AFTN AND EVENING AHEAD OF A WEAKENING FRONT. WINDS WILL BE WEST TO NORTHWEST LESS THAN 10 KNOTS TODAY...THEN BECOME LIGHT TO NEAR CALM THIS EVENING. && .FIRE WEATHER... RED FLAG WARNINGS IN EFFECT THIS AFTERNOON FOR THE EASTERN FLORIDA PANHANDLE AND BIG BEND REGIONS...WITH THE EXCEPTION OF BAY... GULF...AND FRANKLIN COUNTIES FOR EXPECTED LONG DURATIONS OF RH VALUES AT OR BELOW 35 PERCENT. A DRY AIRMASS HAS SETTLED IN ACROSS THE REGION FOR TODAY. THE COMBINATION OF LOW SURFACE DEWPOINTS AND HIGH TEMPERATURES REACHING THE LOWER 70S THIS AFTERNOON IS EXPECTED TO PRODUCE LONG DURATION OF RH VALUES BELOW 35 PERCENT ACROSS MOST OF OUR FLORIDA COUNTIES. SOME INCREASE IN MOISTURE SHOULD HELP KEEP RH VALUES ABOVE CRITICAL THRESHOLDS ON TUESDAY AFTERNOON ACROSS THE EASTERN PANHANDLE...BUT FURTHER EAST INTO PORTIONS OF THE BIG BEND CHANCES FOR CRITICAL THRESHOLDS WILL BE HIGHER. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...RED FLAG WARNING FROM 11 AM CST (12 PM EST) TO 5 PM CST (6 PM EST) TODAY. FIRE WEATHER WATCH FOR A PORTION OF FLORIDA BIG BEND TUESDAY AFTERNOON. FIRE WX WATCH IN EFFECT TUESDAY AFTERNOON FROM 1 PM EST TO 6 PM EST FOR NORTHERN AND EASTERN FLORIDA BIG BEND DUE TO POTENTIAL LONG DURATIONS OF RH VALUES AT OR BELOW 35 PERCENT. GM...NONE && $$ AVIATION/FIRE WEATHER...JAMSKI PUBLIC/MARINE...MROCZKA fl AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LOUISVILLE KY 1031 AM EST MON NOV 13 2006 .UPDATE... LATE MORNING UPDATE WILL PRIMARILY FOCUS ON LOWERING FCST HIGHS FOR TODAY. SCT-BKN LOW CIGS CONTINUE OVER MUCH OF THE NRN 2/3 OF THE CWA. IN ADDITION...BKN-OVC MID LEVEL CLOUDS IN ASSOC WITH APPROACHING UPPER WAVE ARE MOVING INTO THE CWA FROM THE WEST. LATEST RUC LOW LEVEL RH DATA KEEPS THESE CLOUDS IN THROUGH AT LEAST 18Z...VERY STRONG 925MB INVERSION SEEN IN 14Z ACARS SOUNDINGS AT SDF WILL HELP MAINTAIN THEM. HOWEVER WE ARE SEEING A NUMBER OF BREAKS IN THE LOW CIGS (W OF SDF AND IN THE BLUEGRASS) IN LATEST SATELLITE PIX...BUT WILL STILL LOWER FCST HIGHS GIVEN THE SLOW START WE'VE HAD TODAY. RECENT MODELS ARE CONSISTENT IN DISSIPATING PCPN CURRENTLY RUNNING FROM EVV-PAH BEFORE IT GETS INTO OUR DISTRICT. HOWEVER WOULD NOT BE SURPRISED TO SEE SOME SPRINKLES IN OUR FAR W/NW ZONES SO WILL ADD THAT TO THE FCST. AIRMASS IS QUITE DRY OVER THE LMK CWA...SO EASTWARD EXTENT OF ANY PCPN IS QUESTIONABLE. WILL HAVE TO WATCH SHRA DEVELOPING OVER WRN TN AS THEY LIFT OFF TO THE NE. REST OF FCST UNCHANGED AT THIS TIME. UPDATE OUT BY 11 AM EST. CS && .PREV DISCUSSION... (ISSUED 737 AM EST MON NOV 13 2006) UPDATE... SENDING OUT A QUICK UPDATE TO ACCOUNT FOR EXTENSIVE LOW CLOUDS OVER MUCH OF THE LMK CWA AS OF 1230Z. FOLLOWING LATEST RUC...WHICH HAS A DECENT HANDLE ON CURRENT CLOUD DISTRIBUTION...EXPECT SKIES TO REMAIN MOSTLY CLOUDY THIS MORNING. CLOUDS ASSOC WITH UPSTREAM SHORTWAVE MAY KEEP US MOSTLY CLOUDY INTO THE AFTN...WILL EVALUATE THAT WITH THE LATE MORNING UPDATE. CONSENSUS OF MODELS DRIES OUT PCPN CURRENTLY OVER SRN IL/SE MO BEFORE IT REACHES THE LMK CWA...BUT WILL KEEP AN EYE ON IT. UPDATED FCST OUT BY 8 AM EST. CS PREV DISCUSSION... (ISSUED 330 AM EDT MON NOV 13 2006) SHORT TERM (TODAY AND TONIGHT)... MAIN FCST CHALLENGE THIS PERIOD IS CLOUD FCST. STRATOCU IN THE 1 TO 2 FOOT THOUSAND RANGE HAVE CONTD TO SPREAD WNWRD ACRS CENTRAL KY AND SOUTH CENTRAL IN DESPITE MODEL PROGS SHOWING OTHERWISE (SIGNIFICANT RH DECREASE BY 06Z). WINDS AT CLOUD BASE SHUD VEER FROM SE TO SW BY 12UTC...IT APPEARS LO CLOUDS SHUD LIFT TO OUR N IN THE NEXT FEW HRS WITH OVC SKIES CONFINED TO OUR NE SCTNS AFTER SUNRISE. SATELLITE IMAGERY SUPPORTS THIS ATTM WITH OUR 88-D VAD WIND PROFILE SHOWING ESE WINDS AT 15K. BKN CI HAS OVERSPREAD THE LOW CLOUDS ACRS NRN SECTIONS OF OUR FA AND THAT SHUD BE THE DOMINANT CLOUD AT SUNRISE. NETWORK RADARS TO OUR WEST INDICATING SHOWERS ACRS MO AND WRN IL AHEAD OF SHRTWV TROF ACRS THE CENTRAL PLAINS AND ERN KS CDFNT. THAT TROF PROGGED TO WEAKEN AS IT REACHES ERN IL THIS AFTN WITH MS VLY TROF...JUST IN ARREARS...MOVG THRU OUR FA EARLY TNGT. GFS HAS A BETTER HANDLE ON THE SHOWERS SHOWING DEEPER MSTR ACRS MO ATTM. CDFNT BECOMES DIFFUSE THIS EVE...REFLECTING WEAKENING UPR LVL FORCING WITH LITTLE OR NO CONVERGENCE RESULTING IN JUST CLOUD DEBRIS OVERSPREADING OUR AREA DURG THE AFTN AND EVE. BASED ON MODEL CROSS SECTIONS AND SATELLITE IMAGERY...IT APPEARS CI WILL OVERSPREAD OUR FA THIS MRNG...LEAST AMOUNT IN THE SOUTH...FOLLOWED BY MID CLOUDS IN THE AFTN AND SCT-BKN LO CLDS TNGT. SO CURRENT FCST OF FILTERED SUNSHINE TDA AND PARTLY CLDY CONDS TNGT LOOKS FINE WITH NO MENTION OF PRECIP. MOS TEMPS TDA/TNGT CLOSE TO ONGOING FCST...SEE NO REASON TO STRAY. MAY HAVE TO DO A SUNRISE UPDATE...IF LO CLOUDS DONT LIFT TO THE N AS EXPECTED. KIRKPATRICK LONG TERM (TUESDAY THROUGH MONDAY)... TUESDAY AND WEDNESDAY... SIGNIFICANT WEATHER CHALLENGES FOR THE EARLY PORTIONS OF THE LONG TERM...HAVE STAYED CLOSE TO A GFS/NAM BLEND THRU THE PERIOD TO WASH OUT SOME OF THE TRACK DIFFERENCES OF THE STRONG SFC LOW WEDNESDAY. THE SREF MEAN ARE LEANING SLIGHTLY MORE TOWARDS THE NAM TRACK...IF THIS WERE TO VERIFY IT WOULD HAVE SOME POSSIBLE RAMIFICATIONS FOR SEVERE THREAT WITH THE SLIGHTLY MORE NORTHERN TRACK. LITTLE ALTERATION TO THE TEMPS GRIDS FOR THE PERIOD FROM PREVIOUS FORECAST. WEAK SHRTWV MOVING THROUGH THE MID OHIO VALLEY AND GREAT LAKES TUESDAY...SOME SCATTERED TO BROKEN CLOUDS WILL BE POSSIBLE THROUGH THE AFTERNOON. DEVELOPING LOW ACROSS THE SOUTH CENTRAL PLAINS NEAR OKC TUESDAY EVENING WILL START TO MOVE NORTHEAST...INCREASING CLOUDINESS FROM SW TO NE DURING THE OVERNIGHT PERIOD. PRECIP CHANCES LOOKS TO HOLD OFF THROUGH THE NIGHT...WITH A CHANCE MAYBE STILL AROUND THE BWG AREA IN THE EARLY MORNING HOURS. PRECIP LOOKS TO OVERSPREAD THE FORECAST DURING THE MORNING INTO THE LUNCH HOUR. THE GFS HAS A SLIGHTLY FURTHER SOUTH TRACK THAN THE NAM AND SREF...HAVE BLENDED AS MENTIONED BEFORE...WITH THE TRACK GOING FROM NEAR MEM TO JUST NORTH OF CINCY. NAM SUGGESTS SOME DRY SLOTTING POSSIBLE IN THE LATE EVENING INTO THE EARLY MORNING HOURS OF THURSDAY...HAVE ADDED SLIGHTLY LOWER POPS HERE...WITH THE MAJORITY OF THE WRAP AROUND MOISTURE LOOKING TO STAY NEAR OR NORTH OF THE OHIO RIVER...HAVE KEPT HIGHER POPS ACROSS THE NORTH LATE WEDNESDAY NIGHT. RAW MODEL DATA WOULD SUGGEST THAT THE PREVIOUS THINKING OF A MIX IN P-TYPE LOOKS IN JEOPARDY AS THE LOW DOESN'T TAP ANY REALLY COLD AIR...BOUNDARY LAYER TEMPS DON'T GET MUCH BELOW 40 DEGREES AND THE H850 TEMPS ONLY DROP TO -2 OR SO AT THE COLDEST...NOT GOOD CONDITIONS FOR FROZEN PRECIP. MORE IMPORTANTLY IS THE SEVERE THREAT FOR WEDNESDAY...SPC HAS BROUGHT THE SLIGHT RISK REGION JUST TO THE SOUTH OF THE REGION IN MIDDLE TN...IF THE TRACK BECOMES FURTHER NORTH...CLOSER TO THE NAM THEN THIS THREAT AREA COULD BE ADJUSTED TO CONTAIN SOUTHERN KY...THE DYNAMICS OF THIS SYSTEM ARE VERY IMPRESSIVE WITH A STRONG LOW LEVEL JET AND INCREDIBLE SHEAR GENERATED BY THE STRONG WESTERLY COMPONENT OF THE H500 AND H250 JETS. THE ISSUE WILL BE INSTABILITY...IT LOOKS HARD TO COME BY...BUT IF THE NORTHERLY TRACK HITS THEN ENOUGH MAY BE THERE TO MIX DOWN SOME STRONG WINDS...OR WITH THE SIGNIFICANT SHEAR EVEN A TORNADO OR TWO AS LOW TOPPED SUPERCELLS WOULD BE POSSIBLE...THOUGH AS IT STANDS RIGHT NOW THIS SCENARIO IS NOT THE PREFERRED SOLUTION. IT WILL BE IMPORTANT TO WATCH THE DETAILS OF THIS SYSTEM CAREFULLY OVER THE NEXT 48 HOURS. THURSDAY THROUGH MONDAY... OVERALL THE PATTERN THE LAST FEW DAYS HAS ONLY HAD THE TREND OF SOME INCREASED TROUGH ACROSS THE EASTERN THIRD OF THE CONUS FOR NEXT WEEKEND...OTHER THAN THAT A FAIRLY STABLE SET OF SOLUTIONS. THE OPERATIONAL 00Z EURO AND GFS ARE IN PRETTY DECENT AGREEMENT THRU FRIDAY...THEN THEY START TO VEER FROM EACH OTHER BY EARLY NEXT WEEK. THE MORE CONSISTENT OF THE TWO SOLUTIONS FOR NEXT WEEK IS FOUND USING THE GFS AND ITS ENSEMBLE MEAN...AS THE EURO HAS BEEN HAVING SOME ISSUES DEALING WITH THE TROUGH FROM THE WEEKEND AND THEN THE WESTERN ATLANTIC PATTERN AS A WHOLE...THOUGH UNUSUALLY STRONG AGREEMENT FOUND IN THE PACIFIC LATE IN THE PERIOD. WILL BE USING A BLEND OF THE 00Z GFS AND 00Z EURO INTO FRIDAY...THEN MOVING WHOLLY TOWARDS THE VERY STABLE GFS ENSEMBLE SOLUTION FROM LATER FRIDAY INTO EARLY NEXT WEEK. THE EURO IS SLIGHTLY FASTER MOVING THE CLOSED LOW INTO QUEBEC BY LATE THURSDAY AND THEN TOWARDS JAMES BAY BY FRIDAY...CLOUDS LOOK TO FINALLY EXIT THE REGION LATE FRIDAY MORNING AS SFC HI BUILDS ACROSS THE SE CONUS STATES. WARP AROUND PRECIP SHOULD LINGER INTO THURSDAY...ENDING BY THE EARLY EVENING HOURS AND SHOULD BE MORE LIKELY ACROSS THE NORTHERN PORTIONS OF THE FORECAST AREA. COOL AREA OF CANADIAN HI PRESSURE STARTS TO DRIFT SE FROM THE NORTHERN ROCKIES SATURDAY AS A DRY FRONT MOVES ACROSS THE REGION...THOUGH THE OPER GFS SHOWS PRECIP HAVE NOT MENTIONED AS THE ENS MEAN SHOWS THE POPS WELL LESS THAN CLIMO. COOL NORTHERLY FLOW LOOKS TO STICK AROUND SUNDAY AND MONDAY AS CANADIAN HIGH MOVES ACROSS THE CENTRAL PLAINS INTO THE SOUTHERN STATES BY MONDAY. AGAIN THE GFS HINTING AT SOME MOISTURE FROM THE LAKES WORKING SOUTH...COVERAGE WOULD BE REMARKABLY SMALL...AND MORE LIKELY ACROSS E KY AND ENS POPS ARE AGAIN MUCH LOWER THAN CLIMO...WILL LEAVE DRY SUNDAY IN THE EAST AS WELL. SUNNY SKIES LOOK LIKELY. TEMPS SATURDAY THRU MONDAY LOOK TO BE 4 TO 8 DEGREES BELOW NORMAL THROUGH THE PERIOD WITH SOME MORNINGS AT OR BELOW FREEZING. HAVE LEANED MORE TOWARDS THE GFS AND ENS GFS LATER IN THE PERIOD FOR THE CONSISTENCY IT HAS SHOWN THERE...BUT ALSO IT SEEMS TO BE HANDLING THE STRONG PAC JET COMING ONSHORE LATE INTO THE WEEKEND AND DRIVING ACROSS THE NORTHERN TIER STATES INTO EARLY NEXT WEEK...THUS CREATING THE FLATTER SOLUTION ACROSS THE CONUS AND THE DEEP TROUGH SEEN MORE PROGRESSIVE INTO THE ATLC BY TUESDAY. TRAVEL AROUND TURKEY DAY EVE STILL LOOKS GOOD...AND TEMPS LOOK TO BE MUCH WARMER AS WE APPROACH THANKSGIVING. SCHOTT && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 1019 AM EST MON NOV 13 2006 .DISCUSSION... CHALLENGE FOR THE DAY IS THE PERSISTENT STRATUS DECK THAT COVERS EASTERN KY. VISIBLE SATELLITE SHOWS HIGHER MOUNTAINS IN LETCHER...HARLAN...AND BELL COUNTY EXTENDING ABOVE THE CLOUDS. THIS IS ALSO VERIFIED WITH WEB CAM ON MOUNTAINS NEAR MIDDLESBORO. CEILINGS ARE GENERALLY BELOW 1000 FEET...AND BASED ON 12Z SOUNDINGS...AND OBSERVATIONS NOTED ABOVE...THE CLOUDS ARE ONLY ABOUT 1000 FEET THICK. WITH VERY STRONG INVERSION PRESENT AND FORECAST TO PERSIST THE CLOUDS WILL BE VERY SLOW TO BREAK UP...EVEN THOUGH THEY ARE SHALLOW IN DEPTH. THE 12Z NAM AND LATEST RUC DO NOT HAVE A GOOD HANDLE ON THE MOISTURE AT 925 MB...BUT NAM LOOKS BEST AND INDICATES LITTLE CHANGE IN MOISTURE PATTERN UNTIL MID AFTERNOON. WITH ALL THIS IN MIND WILL UPDATE GRIDS AND ASSOCIATED FORECAST PRODUCTS TO ACCOUNT FOR MORE CLOUDS INTO THE AFTERNOON. PREVIOUS FORECAST HAD ALREADY LOWERD MAX TEMPS FROM GUIDANCE. THE 12Z MET AND FWC FORECAST MOS TEMPS FOR THIS AFTERNOON STILL LOOK TOO HIGH. HAVE LOWERED MAX TEMPERATURE FORECAST A FEW MORE DEGREES. && .PREV DISCUSSION... 559 AM EST MON NOV 13 2006 PERSISTENT STRATOCU HAVE BEEN VERY SLOW TO SCATTER OUT OVERNIGHT IN THE FAR SW COUNTIES AND HANGS ON OVER THE REST OF THE CWA. SME AND EKQ HAVE GONE CLEAR...WHILE 1A6 DID FOR A TIME...BUT SC ADVECTED BACK TO THE WEST ON THE E TO ESE FLOW BETWEEN THE WEAKENING RIDGE OF HIGH PRESSURE AND A TROUGH EXTENDING THROUGH THE PLAINS. THE CLEARING IS NEAR LOZ...BUT CLOUDS HAVE ADVECTED BACK TO THE WEST THERE. IN ADDITION...THE SOUTHERN EXTENT OF THE STRATOCU IN NE TN ALSO SEEMS TO BE ADVANCING TO THE NORTH. THE WESTERN EDGE OF THE STRATOCU IS ABOUT 25 MILES WEST OF I 65. HOWEVER...HIGH AND SOME MID CLOUDS WERE WORKING EAST ACROSS THE MS VALLEY AND INTO THE OH VALLEY IN ADVANCE OF A SW/V TROUGH ASSOCIATED WITH THE ABOVE MENTIONED SFC TROUGH. THE MAIN WEATHER MAKER FOR THIS FORECAST IS THE SYSTEM WORKING ONTO THE WEST COAST ATTM. THE BIGGEST FORECAST CHALLENGE EARLY IN THE PERIOD IS THE EROSION OF THE STRATOCU TRAPPED BELOW THE SUBSIDENCE INVERSION. THE RELATIVELY WEAK NOVEMBER SUNSHINE SHOULD BE SLOW TO HELP ERODE THESE CLOUDS AWAY TODAY...WHEN COMBINED WITH THE HIGH AND MID CLOUDS WORKING IN. THE CLEARING IN THE SW COUNTIES OVERNIGHT IS PROMISING AND IN GENERAL...EXPECT SOME GRADUAL CLEARING FROM SW TO NE THROUGHOUT THE DAY THOUGH FAIRLY DENSE CIRRUS AND SOME OCCASIONAL AC SHOULD WORK ACROSS THE REGION TODAY. CLEARING OF THE SC MAY NOT REACH THE FAR EASTERN AND NE COUNTIES UNTIL THE 18 TO 21Z TIME FRAME. THE SC COMBINED WITH THE SIGNIFICANT HIGH AND SOME MID CLOUDS WILL HOLD BACK TEMPS SUBSTANTIALLY AND HAVE UNDERCUT MAV NUMBERS BY SEVERAL DEGREES ACROSS THE BOARD AS THE GFS APPEARS TO HAVE A POOR HANDLE ON THE SC. OPTED TO GO MORE IN LINE WITH A COMPROMISE BETWEEN THE COOLER FWC/MAV NUMBERS. WEAKENING SFC HIGH PRESSURE WITH SW/V RIDGING WORKING INTO THE REGION LATER TONIGHT SHOULD LEAD TO CLEAR SKIES AND LIGHT WINDS. A SMALL RIDGE/VALLEY TEMPERATURE SPLIT APPEARS IN STORE WITH RELATIVELY DRY AIR IN PLACE...DEWPOINTS EXPECTED TO BE IN THE LOWER 30S...AND GOOD RADIATIONAL COOLING CONDITIONS ESPECIALLY DURING THE SECOND HALF OF THE NIGHT. VALLEY LOCATIONS SHOULD DECOUPLE AND COOL INTO THE LOWER 30S...WITH RIDGETOPS HOLDING IN THE UPPER 30S. MODERATING TEMPERATURES ARE EXPECTED ON TUESDAY WITH MORE SUNSHINE OVERALL THAN TODAY...WITH WEAK SFC RIDGING IN PLACE. THE MAIN WEATHER MAKER FOR THIS FORECAST PERIOD IS EXPECTED TO BEGIN TO REALLY TAKE SHAPE TO THE LEE OF THE ROCKIES ON TUESDAY AFTERNOON. A SW/V THAT SHOULD ENTER THE PACIFIC NW LATER TODAY...AND MOVE THROUGH THE ROCKIES IS EXPECTED TO DEEPEN THE EASTWARD MOVING MID LEVEL SW/V AND HELP CLOSE OFF A MID LEVEL LOW OVER THE SOUTHERN PLAINS ON TUESDAY NIGHT. AT THE SAME TIME THE SFC LOW SHOULD REORGANIZE OVER THE OK/AR AREA AND THEN TRACK NE TO OZARKS/SW MO AREA BY 12Z ON WED. PRECIPITATION ON ISENTROPIC LIFT SHOULD OVERSPREAD MIDDLE TN AND THE CUMBERLAND PLATEAU AND THREATEN AREAS TO THE WEST OF I 75 BY AROUND SUNRISE ON WED IN ADVANCE OF THIS SYSTEM. AN AREA OF RELATIVELY STRONG ISENTROPIC LIFT SHOULD REACH THE NE COUNTIES BY WED AFTERNOON AS THE WARM FRONT LIFTS N INTO THE REGION. GFS/NAM AND 13/21Z SREF ARE CONSISTANT IN BRINGING THE PRECIPITATION ACROSS THE REGION ON WED AND THEN WED NIGHT AS THE COLD FRONT CROSSES THE AREA. OPTED TO RAISE POPS HIGHER...INTO THE CAT RANGE ON WED AND WED NIGHT. 0Z MET WAS INTO THE CAT RANGE FOR WED...WITH THE 6Z MAV NOW CAT ON WED. 12 HOUR MEX POPS FOR WED NIGHT WERE CAT AS WELL. OVERALL...QPF FOR THE EVENT SHOULD BE IN THE 0.50 TO 0.80" RANGE...BRINGING BENEFITIAL RAIN AND HELPING TO KEEP FOREST FUELS MOIST. EXTENDED...OVERALL THE EXTENDED FORECAST WAS IN GOOD SHAPE AND MADE LITTLE IF ANY ADJUSTMENTS. OPTED TO RAISE POPS IN THE N ON THU (AREA THAT WILL BE CLOSEST TO THE MID LEVEL LOW CENTER TO THE LIKELY RANGE FOR THU. OTHERWISE...INCLUDED THE CHANCE FOR SOME SNOW SHOWERS ON THU NIGHT ACROSS THE HIGHEST ELEVATIONS NEAR THE TN LINE AS GFS/ECMWF FORECAST SUB 0C 8H TEMPS. 911 PM EST SUN NOV 12 2006 AREA OF SURFACE HIGH PRESSURE IS CURRENTLY NOSED IN ACROSS THE OHIO VALLEY FROM THE NORTH. STRATOCUMULUS DECK HAS BEEN A JUGGERNAUT AS MOISTURE REMAINS TRAPPED BELOW A VERY POTENT INVERSION BETWEEN 925 AND 850 MB. IN FACT...SATELLITE TRENDS OVER THE PAST FEW HOURS HAVE SHOWN A SLIGHT EXPANSION OF THE DECK TO THE WEST. UPPER AIR CHARTS AND VAD WIND PROFILES CONFIRM THE NORTHEAST FLOW IN PLACE AT THE LOW LEVELS. THIS FLOW PATTERN IS PROGGED TO HOLD TRUE FOR THE REST OF THE NIGHT. AS SUCH...WILL KEEP CLOUDY SKIES ACROSS THE AREA FOR THE REST OF THE NIGHT AND INTO EARLY TOMORROW MORNING. CONSEQUENTLY...WILL REMOVE THE MENTION OF FOG...INCREASE LOW TEMPERATURES TO THE MID 30S TONIGHT AND INCLUDE SOME LOWER RANGED NUMBERS FOR TOMORROWS HIGHS...PARTICULARLY IN THE EAST...WHERE A CLEAR START IS UNLIKELY. UPDATE OUT BEFORE TOO LONG. 524 PM EST SUN NOV 12 2006 SATELLITE TRENDS ARE A BIT SLOWER WITH THE CLEARING OVER THE PAST HOUR OR SO. AS SUCH...WILL UPDATE TO MENTION MOSTLY CLOUDY TO CLOUDY SKIES EARLY IN THE EVENING. WILL REASSESS CLEARING AND FOG POTENTIAL AS WELL AS LOW TEMPERATURES A BIT LATER. UPDATE OUT SHORTLY. 131 PM EST SUN NOV 12 2006 SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT... CLOUDS HAVE BEEN PERSISTENT...HENCE TEMPS NEVER REACHED EXPECTED VALUES. SOME EVIDENCE OF THINNING WITH CLEARING WEST OF I65 AND A FEW BREAKS IN OUR ERN HALF OF THE CWFA. EXPECT THE BREAKS TO BECOME MORE EVIDENT OVERNIGHT WITH CLEARING AFTER MIDNIGHT. TEMPS WILL HAVE A SLOW START TO OVERNIGHT LOWS AND HAVE RAISED NUMBERS TO AROUND 30 MOST AREAS. EXPECT LOWER VALUES IN OUR SW WHERE CLEARING WILL BE EARLIER. PARTLY CLOUDY ON MON WITH COLD CU SHOULD ALLOW TEMPS TO CLIMB INTO THE MID 50S AND WITH WINDS SHIFTING TO THE S/SW FOR TUE...LOOK FOR HIGHS NEAR 60. MODELS CONSISTENT WITH RIDGE BUILDING INTO OH VLY FOR THE NEAR TERM AND NEXT TROF TO FORM ON THE LEE SIDE OF ROCKIES THEN MOVING ACROSS PLAINS ON TUE. SOUTHERLY FLOW WILL INCREASE MOISTURE FOR TUE AND SOME ISENTROPIC LIFT TO BRING INCREASED CLOUD COVER. PCPN SHOULD APPEAR ON THE HORIZON TUE NIGHT AND HAVE INTRODUCED POPS AFTER MIDNIGHT. SW COUNTIES WILL BE THE FIRST TO SEE PCPN AND THOUGH GFS IS A TAD FASTER THAN NAM BOTH MODELS AGREE THAT THERE SHOULD BE SOME PCPN TO AFFECT THE AREA...ESP SCNTRL KY...BY DAWN ON WED. LONG TERM...WEDNESDAY THROUGH SUNDAY... DEEP TROUGH IS PROGGED TO AMPLIFY OVER THE EASTERN U.S. WEDNESDAY THROUGH FRIDAY BEFORE RELAXING SOMEWHAT FOR THE WEEKEND. CONFIDENCE IS HIGHER THAN NORMAL DUE TO GOOD MODEL AGREEMENT ON DETAILS EARLY IN THE PERIOD...HOWEVER CONFIDENCE LEVEL WANES FROM FRIDAY ON. AS DEEP UPPER LEVEL LOW FORMS OVER THE LOWER OHIO VALLEY WEDNESDAY AND THURSDAY...A STRONG SURFACE LOW AND COLD FRONT WILL MOVE ACROSS EASTERN KENTUCKY WEDNESDAY AND WEDNESDAY NIGHT AND WILL CONTINUE LIKELY POPS. DYNAMICS ARE STRONG ENOUGH TO JUSTIFY A CHANCE OF THUNDERSTORMS AS WELL. THE POSITION OF THE VERTICALLY STACKED LOW MOVING BY JUST TO OUR NORTH AND NORTHEAST BRINGS WRAP-AROUND MOISTURE AND COLD AIR ADVECTION ON THURSDAY WITH TEMPS PROBABLY NOT BUDGING MUCH FROM THE LOW TO MID 40S AT THE LOWER ELEVATIONS. SOME SNOW MAY MIX IN WITH THE RAIN THURSDAY NIGHT...ESPECIALLY OVER THE HIGHER ELEVATIONS. THE LOW GRADUALLY LIFTS OFF TO THE NORTHEAST FRIDAY WITH A BRIEF PERIOD OF SURFACE RIDGING UNTIL THE NEXT IMPULSE DIVES DOWN INTO THE TROUGH SATURDAY AND SUNDAY...SO WILL BRING IN A SLIGHT CHANCE OF SHOWERS AND CONTINUE THE BELOW NORMAL TEMPS THROUGH THE WEEKEND. COULD BE SOME SNOW MIXED IN WITH THIS AS WELL ESPECIALLY OVERNIGHT SATURDAY NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SBH ky AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LOUISVILLE KY 737 AM EST MON NOV 13 2006 .UPDATE... SENDING OUT A QUICK UPDATE TO ACCOUNT FOR EXTENSIVE LOW CLOUDS OVER MUCH OF THE LMK CWA AS OF 1230Z. FOLLOWING LATEST RUC...WHICH HAS A DECENT HANDLE ON CURRENT CLOUD DISTRIBUTION...EXPECT SKIES TO REMAIN MOSTLY CLOUDY THIS MORNING. CLOUDS ASSOC WITH UPSTREAM SHORTWAVE MAY KEEP US MOSTLY CLOUDY INTO THE AFTN...WILL EVALUATE THAT WITH THE LATE MORNING UPDATE. CONSENSUS OF MODELS DRIES OUT PCPN CURRENTLY OVER SRN IL/SE MO BEFORE IT REACHES THE LMK CWA...BUT WILL KEEP AN EYE ON IT. UPDATED FCST OUT BY 8 AM EST. CS && .PREV DISCUSSION... (ISSUED 330 AM EDT MON NOV 13 2006) SHORT TERM (TODAY AND TONIGHT)... MAIN FCST CHALLENGE THIS PERIOD IS CLOUD FCST. STRATOCU IN THE 1 TO 2 FOOT THOUSAND RANGE HAVE CONTD TO SPREAD WNWRD ACRS CENTRAL KY AND SOUTH CENTRAL IN DESPITE MODEL PROGS SHOWING OTHERWISE (SIGNIFICANT RH DECREASE BY 06Z). WINDS AT CLOUD BASE SHUD VEER FROM SE TO SW BY 12UTC...IT APPEARS LO CLOUDS SHUD LIFT TO OUR N IN THE NEXT FEW HRS WITH OVC SKIES CONFINED TO OUR NE SCTNS AFTER SUNRISE. SATELLITE IMAGERY SUPPORTS THIS ATTM WITH OUR 88-D VAD WIND PROFILE SHOWING ESE WINDS AT 15K. BKN CI HAS OVERSPREAD THE LOW CLOUDS ACRS NRN SECTIONS OF OUR FA AND THAT SHUD BE THE DOMINANT CLOUD AT SUNRISE. NETWORK RADARS TO OUR WEST INDICATING SHOWERS ACRS MO AND WRN IL AHEAD OF SHRTWV TROF ACRS THE CENTRAL PLAINS AND ERN KS CDFNT. THAT TROF PROGGED TO WEAKEN AS IT REACHES ERN IL THIS AFTN WITH MS VLY TROF...JUST IN ARREARS...MOVG THRU OUR FA EARLY TNGT. GFS HAS A BETTER HANDLE ON THE SHOWERS SHOWING DEEPER MSTR ACRS MO ATTM. CDFNT BECOMES DIFFUSE THIS EVE...REFLECTING WEAKENING UPR LVL FORCING WITH LITTLE OR NO CONVERGENCE RESULTING IN JUST CLOUD DEBRIS OVERSPREADING OUR AREA DURG THE AFTN AND EVE. BASED ON MODEL CROSS SECTIONS AND SATELLITE IMAGERY...IT APPEARS CI WILL OVERSPREAD OUR FA THIS MRNG...LEAST AMOUNT IN THE SOUTH...FOLLOWED BY MID CLOUDS IN THE AFTN AND SCT-BKN LO CLDS TNGT. SO CURRENT FCST OF FILTERED SUNSHINE TDA AND PARTLY CLDY CONDS TNGT LOOKS FINE WITH NO MENTION OF PRECIP. MOS TEMPS TDA/TNGT CLOSE TO ONGOING FCST...SEE NO REASON TO STRAY. MAY HAVE TO DO A SUNRISE UPDATE...IF LO CLOUDS DONT LIFT TO THE N AS EXPECTED. KIRKPATRICK LONG TERM (TUESDAY THROUGH MONDAY)... TUESDAY AND WEDNESDAY... SIGNIFICANT WEATHER CHALLENGES FOR THE EARLY PORTIONS OF THE LONG TERM...HAVE STAYED CLOSE TO A GFS/NAM BLEND THRU THE PERIOD TO WASH OUT SOME OF THE TRACK DIFFERENCES OF THE STRONG SFC LOW WEDNESDAY. THE SREF MEAN ARE LEANING SLIGHTLY MORE TOWARDS THE NAM TRACK...IF THIS WERE TO VERIFY IT WOULD HAVE SOME POSSIBLE RAMIFICATIONS FOR SEVERE THREAT WITH THE SLIGHTLY MORE NORTHERN TRACK. LITTLE ALTERATION TO THE TEMPS GRIDS FOR THE PERIOD FROM PREVIOUS FORECAST. WEAK SHRTWV MOVING THROUGH THE MID OHIO VALLEY AND GREAT LAKES TUESDAY...SOME SCATTERED TO BROKEN CLOUDS WILL BE POSSIBLE THROUGH THE AFTERNOON. DEVELOPING LOW ACROSS THE SOUTH CENTRAL PLAINS NEAR OKC TUESDAY EVENING WILL START TO MOVE NORTHEAST...INCREASING CLOUDINESS FROM SW TO NE DURING THE OVERNIGHT PERIOD. PRECIP CHANCES LOOKS TO HOLD OFF THROUGH THE NIGHT...WITH A CHANCE MAYBE STILL AROUND THE BWG AREA IN THE EARLY MORNING HOURS. PRECIP LOOKS TO OVERSPREAD THE FORECAST DURING THE MORNING INTO THE LUNCH HOUR. THE GFS HAS A SLIGHTLY FURTHER SOUTH TRACK THAN THE NAM AND SREF...HAVE BLENDED AS MENTIONED BEFORE...WITH THE TRACK GOING FROM NEAR MEM TO JUST NORTH OF CINCY. NAM SUGGESTS SOME DRY SLOTTING POSSIBLE IN THE LATE EVENING INTO THE EARLY MORNING HOURS OF THURSDAY...HAVE ADDED SLIGHTLY LOWER POPS HERE...WITH THE MAJORITY OF THE WRAP AROUND MOISTURE LOOKING TO STAY NEAR OR NORTH OF THE OHIO RIVER...HAVE KEPT HIGHER POPS ACROSS THE NORTH LATE WEDNESDAY NIGHT. RAW MODEL DATA WOULD SUGGEST THAT THE PREVIOUS THINKING OF A MIX IN P-TYPE LOOKS IN JEOPARDY AS THE LOW DOESN'T TAP ANY REALLY COLD AIR...BOUNDARY LAYER TEMPS DON'T GET MUCH BELOW 40 DEGREES AND THE H850 TEMPS ONLY DROP TO -2 OR SO AT THE COLDEST...NOT GOOD CONDITIONS FOR FROZEN PRECIP. MORE IMPORTANTLY IS THE SEVERE THREAT FOR WEDNESDAY...SPC HAS BROUGHT THE SLIGHT RISK REGION JUST TO THE SOUTH OF THE REGION IN MIDDLE TN...IF THE TRACK BECOMES FURTHER NORTH...CLOSER TO THE NAM THEN THIS THREAT AREA COULD BE ADJUSTED TO CONTAIN SOUTHERN KY...THE DYNAMICS OF THIS SYSTEM ARE VERY IMPRESSIVE WITH A STRONG LOW LEVEL JET AND INCREDIBLE SHEAR GENERATED BY THE STRONG WESTERLY COMPONENT OF THE H500 AND H250 JETS. THE ISSUE WILL BE INSTABILITY...IT LOOKS HARD TO COME BY...BUT IF THE NORTHERLY TRACK HITS THEN ENOUGH MAY BE THERE TO MIX DOWN SOME STRONG WINDS...OR WITH THE SIGNIFICANT SHEAR EVEN A TORNADO OR TWO AS LOW TOPPED SUPERCELLS WOULD BE POSSIBLE...THOUGH AS IT STANDS RIGHT NOW THIS SCENARIO IS NOT THE PREFERRED SOLUTION. IT WILL BE IMPORTANT TO WATCH THE DETAILS OF THIS SYSTEM CAREFULLY OVER THE NEXT 48 HOURS. THURSDAY THROUGH MONDAY... OVERALL THE PATTERN THE LAST FEW DAYS HAS ONLY HAD THE TREND OF SOME INCREASED TROUGH ACROSS THE EASTERN THIRD OF THE CONUS FOR NEXT WEEKEND...OTHER THAN THAT A FAIRLY STABLE SET OF SOLUTIONS. THE OPERATIONAL 00Z EURO AND GFS ARE IN PRETTY DECENT AGREEMENT THRU FRIDAY...THEN THEY START TO VEER FROM EACH OTHER BY EARLY NEXT WEEK. THE MORE CONSISTENT OF THE TWO SOLUTIONS FOR NEXT WEEK IS FOUND USING THE GFS AND ITS ENSEMBLE MEAN...AS THE EURO HAS BEEN HAVING SOME ISSUES DEALING WITH THE TROUGH FROM THE WEEKEND AND THEN THE WESTERN ATLANTIC PATTERN AS A WHOLE...THOUGH UNUSUALLY STRONG AGREEMENT FOUND IN THE PACIFIC LATE IN THE PERIOD. WILL BE USING A BLEND OF THE 00Z GFS AND 00Z EURO INTO FRIDAY...THEN MOVING WHOLLY TOWARDS THE VERY STABLE GFS ENSEMBLE SOLUTION FROM LATER FRIDAY INTO EARLY NEXT WEEK. THE EURO IS SLIGHTLY FASTER MOVING THE CLOSED LOW INTO QUEBEC BY LATE THURSDAY AND THEN TOWARDS JAMES BAY BY FRIDAY...CLOUDS LOOK TO FINALLY EXIT THE REGION LATE FRIDAY MORNING AS SFC HI BUILDS ACROSS THE SE CONUS STATES. WARP AROUND PRECIP SHOULD LINGER INTO THURSDAY...ENDING BY THE EARLY EVENING HOURS AND SHOULD BE MORE LIKELY ACROSS THE NORTHERN PORTIONS OF THE FORECAST AREA. COOL AREA OF CANADIAN HI PRESSURE STARTS TO DRIFT SE FROM THE NORTHERN ROCKIES SATURDAY AS A DRY FRONT MOVES ACROSS THE REGION...THOUGH THE OPER GFS SHOWS PRECIP HAVE NOT MENTIONED AS THE ENS MEAN SHOWS THE POPS WELL LESS THAN CLIMO. COOL NORTHERLY FLOW LOOKS TO STICK AROUND SUNDAY AND MONDAY AS CANADIAN HIGH MOVES ACROSS THE CENTRAL PLAINS INTO THE SOUTHERN STATES BY MONDAY. AGAIN THE GFS HINTING AT SOME MOISTURE FROM THE LAKES WORKING SOUTH...COVERAGE WOULD BE REMARKABLY SMALL...AND MORE LIKELY ACROSS E KY AND ENS POPS ARE AGAIN MUCH LOWER THAN CLIMO...WILL LEAVE DRY SUNDAY IN THE EAST AS WELL. SUNNY SKIES LOOK LIKELY. TEMPS SATURDAY THRU MONDAY LOOK TO BE 4 TO 8 DEGREES BELOW NORMAL THROUGH THE PERIOD WITH SOME MORNINGS AT OR BELOW FREEZING. HAVE LEANED MORE TOWARDS THE GFS AND ENS GFS LATER IN THE PERIOD FOR THE CONSISTENCY IT HAS SHOWN THERE...BUT ALSO IT SEEMS TO BE HANDLING THE STRONG PAC JET COMING ONSHORE LATE INTO THE WEEKEND AND DRIVING ACROSS THE NORTHERN TIER STATES INTO EARLY NEXT WEEK...THUS CREATING THE FLATTER SOLUTION ACROSS THE CONUS AND THE DEEP TROUGH SEEN MORE PROGRESSIVE INTO THE ATLC BY TUESDAY. TRAVEL AROUND TURKEY DAY EVE STILL LOOKS GOOD...AND TEMPS LOOK TO BE MUCH WARMER AS WE APPROACH THANKSGIVING. SCHOTT && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 611 AM CST MON NOV 13 2006 FXUS63 KMPX 130903 AFDMPX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 303 AM CST MON NOV 13 2006 .DISCUSSION... PRECIPITATION ASSOCIATED WITH MID LEVEL SHORTWAVE/FRONTOGENESIS CONTINUES TO SHIFT EAST ACROSS THE FA THIS MORNING. THE RUC/NAM/GFS MODELS ALL FORECAST THIS AREA TO EXIT THE EASTERN CWA BY MID MORNING...SO POPS HAVE BEEN ALIGNED ACCORDINGLY...WITH 20-30 POPS ENDING ACROSS THE WI COUNTIES BY 15Z. HAVE MAINTAINED COLDER HIGH TEMPERATURES ACROSS THE SOUTH/EAST TODAY...TAKING INTO CONSIDERATION THE LINGERING CLOUD COVER AND SNOWPACK. MOSTLY CLEAR SKIES ACROSS THE WEST SHOULD YIELD RELATIVELY WARMER READINGS IN THE MID/UPPER 40S. THE PATTERN WILL REMAIN ACTIVE AS A BROAD TROUGH BECOMES ESTABLISHED ACROSS THE CONUS DURING THE BEGINNING OF THE WEEK. NAM/GFS MODELS CONTINUE TO TREND SOUTHWARD WITH THE PLACEMENT OF A SHORTWAVE /AND EVENTUAL CLOSED LOW/ THAT DEEPENS EAST OF THE CENTRAL ROCKIES. MEANWHILE...THE PARENT LOW IS PROGGED TO PASS ACROSS SOUTHERN MANITOBA/SASKATCHEWAN. ASSOCIATED WEAK INVERTED TROUGH SLIDES ACROSS THE FORECAST AREA BETWEEN TUESDAY AFTERNOON AND WEDNESDAY MORNING. HAVE ORIENTED HIGHER CHANCE POPS WITH THE TROUGH...BUT HAVE SCALED BACK SLIGHTLY DUE TO SOUTHWARD TRENDS OF THE MAIN SYSTEM. EXPECT TEMPERATURES TO RETREAT BACK BELOW NORMAL ON WEDNESDAY/WEDNESDAY NIGHT. DRY WEATHER IS EXPECTED FOR THURSDAY AS WEAK MID LEVEL RIDGING BUILDS ACROSS THE CENTRAL UNITED STATES. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ LS mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1037 AM EST MON NOV 13 2006 .SHORT TERM /REST OF TODAY THROUGH TONIGHT/... LOW LEVEL MOISTURE REMAINS TRAPPED UNDER STRONG INVERSION. BACK EDGE OF ST IS ON THE IL/IN BORDER ATTM. EVEN IF INVERSION DOES BREAK THERE IS A LOT OF MID CLOUDS STREAMING OVER. ADDITIONAL MOISTURE ASSOCIATED WITH CDFNT IN IL IS WORKING E QUICKLY. INCREASED CLOUD COVER TODAY AND TONIGHT. IN ADDITION...LOWERED TEMPS FOR TODAY A LITTLE...ESPECIALLY IN THE NW WHERE TEMPERATURES WERE RUNNING WELL BELOW THE CURVE. SITES && .PREV DISCUSSION... /ISSUED 639 AM EST MON NOV 13 2006/ AVIATION /12Z-12Z/... 06Z NAM/GFS SOLNS HAVE PICKED UP ON CURRENT LOCATION OF SC DECK A LITTLE BIT BETTER THAN PREV RUNS. HOWEVER...OVERALL CONFIDENCE IN CLOUD FCST REMAINS LOW. BEGINNING TO THINK THAT MVFR CIGS WILL HOLD FOR MUCH OF THE DAY YET AGAIN TODAY AS LO LVL FLO REMAINS FAIRLY LIGHT ALL DAY AHEAD OF APPCHG WEAK FRNTL BNDRY. EASTERLY FLO IN BNDRY LYR BEGINNING TO SLACK AND VEER TO SRLY...BUT BACK EDGE OF SC DECK HAS NOW BEEN PUSHED WEST ALL THE WAY INTO CNTRL INDIANA/KENTUCKY. MODEL SOUNDINGS KEEPING INVERSION STRONGER THAN PREV THOUGHT WITH NOT AS MUCH BNDRY LYR MIXING. KCVG/KLUK PROBABLY HAVE THE BEST SHOT TO BREAK OUT OF MVFR CIGS BY MID/LATE AFTN...BEING REPLACED BY EXTENSIVE AC DECK AHEAD OF FRNTL BNDRY. AT THE OTHER TAF SITES...WILL MAINTAIN MVFR CIGS INTO THE EVNG HOURS. BNDRY APPEARS TO WASH OUT ACRS FCST AREA THIS EVNG...BUT INCREASING AMOUNTS OF LO LVL MOISTURE WILL SERVE TO EITHER REESTABLISH OR REINFORCE SC DECK INTO MVFR LEVELS LATE TONIGHT. RYAN PREV DISCUSSION... /ISSUED 301 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH WEDNESDAY/... SURFACE ANALYSIS SHOWS HIGH PRESSURE RIDGE FROM GREAT LAKES INTO THE TENNESSEE VALLEY. SATELLITE IMAGERY SHOWS STRATUS HOLDING TIGHT OVER FORECAST AREA CIRRUS MOVING IN FROM THE WEST. GFS AND NAM ARE IN PRETTY GOOD AGREEMENT THROUGH THE FORECAST PERIOD. WEAK SURFACE HIGH WILL DOMINATE WEATHER THROUGH TUESDAY NIGHT. A DIGGING UPPER TROF WILL QUICKLY DEEPEN A SURFACE LOW AND MOVE IT INTO THE OHIO VALLEY ON WEDNESDAY. THIS WILL BRING PLENTY OF SHOWERS BEGINNING WEDNESDAY AND LASTING INTO THRU FRIDAY NIGHT. GFS 1000-850 THICKNESSES SUGGEST A MIX OF SNOW OR ALL SNOW BY FRIDAY NIGHT. AS FOR TODAYS CLOUD FORECAST IT IS NOT STRAIGHT FORWARD. STRATUS IS STILL HANGING TIGHT WITH HIGH LEVEL CLOUDS WORKING IN FROM THE WEST. NAM/RUC SHOWING RH DECREASING TO SOME DEGREE TODAY. THINK THERE WILL BE SOME MIXING OUT...BUT HIGH LEVEL CLOUDS WILL DETER THAT TO SOME DEGREE ESPECIALLY THIS TIME OF YEAR. THUS WILL GO WITH BECOMING PARTLY CLOUDY/SUNNY FOR THIS AFTERNOON...HOWEVER CONFIDENCE IS NOT REAL HIGH. WILL REMOVE THE MENTION OF THUNDER FOR WEDNESDAY. BOTH THE NAM AND GFS SHOW NO ELEVATED OR SURFACE BASED INSTABILITY. MAV TEMPS LOOK REASONABLE. THE ONLY CHANGES WERE MADE IN THE FIRST AND FIFTH PERIODS WERE MAV WAS LOWERED SEVERAL DEGREES. TIPTON PREV DISCUSSION... /ISSUED 315 PM EST SUN NOV 12 2006/ LONG TERM /WEDNESDAY THROUGH SUNDAY/... LOOKS LIKE MODELS CONTINUE TO SLOW UP SYSTEM FOR MID WEEK WITH ONSET OF PRECIPITATION MAINLY AFTER 06Z WED BUT BETTER CHANCES AFTER 12Z WED. LOW PRESSURE SYSTEM CENTERED OVER WESTERN IL AT AROUND 12Z WED WILL MOVE SLOWLY ESE AS A SECOND LOW DEVELOPS OVER WESTERN SC. THEN THE IL/IN LOW WILL MOV NE ACROSS OH INTO THE GRT LKS BY 18Z THU. THIS COINCIDES WITH THE MOVEMENT OF AN UPPER LEVEL LOW. THE UPPER LEVEL LOW AND SURFACE LOW WILL MOVE WELL NORTH OF THE GRT LKS INTO CANADA FRI THROUGH SUN. THIS WILL KEEP THE REGION IN A NW FLOW WITH THE MINIMAL THREAT FOR RAIN/SNOW SHOWERS THROUGH SUNDAY. BEST CHANCES OF PRECIPITATION WILL BE WED INTO THU NIGHT. A MIX OF RAIN SHOWERS AND SNOW SHOWERS MAY BE SEEN...MAINLY EARLY THU MORNING AND FRIDAY NIGHT. AT THIS TIME...HAVE RESTRICTED MENTION OF SLIGHT CHANCE RAIN/SNOW SHOWERS TO SATURDAY NIGHT IN LATER PERIODS OF EXTENDED. HIGHS START OUT IN THE 50S WED AND LOWS THU IN THE 40S WITH A GENERAL COOLING TREND THROUGH THE REMAINDER OF THE EXTENDED PERIOD. EXPECT HIGHS FOR THE MOST PART IN THE 40S AND LOWS IN THE 30S. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SHORT TERM... oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 639 AM EST MON NOV 13 2006 .AVIATION /12Z-12Z/... 06Z NAM/GFS SOLNS HAVE PICKED UP ON CURRENT LOCATION OF SC DECK A LITTLE BIT BETTER THAN PREV RUNS. HOWEVER...OVERALL CONFIDENCE IN CLOUD FCST REMAINS LOW. BEGINNING TO THINK THAT MVFR CIGS WILL HOLD FOR MUCH OF THE DAY YET AGAIN TODAY AS LO LVL FLO REMAINS FAIRLY LIGHT ALL DAY AHEAD OF APPCHG WEAK FRNTL BNDRY. EASTERLY FLO IN BNDRY LYR BEGINNING TO SLACK AND VEER TO SRLY...BUT BACK EDGE OF SC DECK HAS NOW BEEN PUSHED WEST ALL THE WAY INTO CNTRL INDIANA/KENTUCKY. MODEL SOUNDINGS KEEPING INVERSION STRONGER THAN PREV THOUGHT WITH NOT AS MUCH BNDRY LYR MIXING. KCVG/KLUK PROBABLY HAVE THE BEST SHOT TO BREAK OUT OF MVFR CIGS BY MID/LATE AFTN...BEING REPLACED BY EXTENSIVE AC DECK AHEAD OF FRNTL BNDRY. AT THE OTHER TAF SITES...WILL MAINTAIN MVFR CIGS INTO THE EVNG HOURS. BNDRY APPEARS TO WASH OUT ACRS FCST AREA THIS EVNG...BUT INCREASING AMOUNTS OF LO LVL MOISTURE WILL SERVE TO EITHER REESTABLISH OR REINFORCE SC DECK INTO MVFR LEVELS LATE TONIGHT. RYAN && .PREV DISCUSSION... /ISSUED 301 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH WEDNESDAY/... SURFACE ANALYSIS SHOWS HIGH PRESSURE RIDGE FROM GREAT LAKES INTO THE TENNESSEE VALLEY. SATELLITE IMAGERY SHOWS STRATUS HOLDING TIGHT OVER FORECAST AREA CIRRUS MOVING IN FROM THE WEST. GFS AND NAM ARE IN PRETTY GOOD AGREEMENT THROUGH THE FORECAST PERIOD. WEAK SURFACE HIGH WILL DOMINATE WEATHER THROUGH TUESDAY NIGHT. A DIGGING UPPER TROF WILL QUICKLY DEEPEN A SURFACE LOW AND MOVE IT INTO THE OHIO VALLEY ON WEDNESDAY. THIS WILL BRING PLENTY OF SHOWERS BEGINNING WEDNESDAY AND LASTING INTO THRU FRIDAY NIGHT. GFS 1000-850 THICKNESSES SUGGEST A MIX OF SNOW OR ALL SNOW BY FRIDAY NIGHT. AS FOR TODAYS CLOUD FORECAST IT IS NOT STRAIGHT FORWARD. STRATUS IS STILL HANGING TIGHT WITH HIGH LEVEL CLOUDS WORKING IN FROM THE WEST. NAM/RUC SHOWING RH DECREASING TO SOME DEGREE TODAY. THINK THERE WILL BE SOME MIXING OUT...BUT HIGH LEVEL CLOUDS WILL DETER THAT TO SOME DEGREE ESPECIALLY THIS TIME OF YEAR. THUS WILL GO WITH BECOMING PARTLY CLOUDY/SUNNY FOR THIS AFTERNOON...HOWEVER CONFIDENCE IS NOT REAL HIGH. WILL REMOVE THE MENTION OF THUNDER FOR WEDNESDAY. BOTH THE NAM AND GFS SHOW NO ELEVATED OR SURFACE BASED INSTABILITY. MAV TEMPS LOOK REASONABLE. THE ONLY CHANGES WERE MADE IN THE FIRST AND FIFTH PERIODS WERE MAV WAS LOWERED SEVERAL DEGREES. TIPTON PREV DISCUSSION... /ISSUED 315 PM EST SUN NOV 12 2006/ LONG TERM /WEDNESDAY THROUGH SUNDAY/... LOOKS LIKE MODELS CONTINUE TO SLOW UP SYSTEM FOR MID WEEK WITH ONSET OF PRECIPITATION MAINLY AFTER 06Z WED BUT BETTER CHANCES AFTER 12Z WED. LOW PRESSURE SYSTEM CENTERED OVER WESTERN IL AT AROUND 12Z WED WILL MOVE SLOWLY ESE AS A SECOND LOW DEVELOPS OVER WESTERN SC. THEN THE IL/IN LOW WILL MOV NE ACROSS OH INTO THE GRT LKS BY 18Z THU. THIS COINCIDES WITH THE MOVEMENT OF AN UPPER LEVEL LOW. THE UPPER LEVEL LOW AND SURFACE LOW WILL MOVE WELL NORTH OF THE GRT LKS INTO CANADA FRI THROUGH SUN. THIS WILL KEEP THE REGION IN A NW FLOW WITH THE MINIMAL THREAT FOR RAIN/SNOW SHOWERS THROUGH SUNDAY. BEST CHANCES OF PRECIPITATION WILL BE WED INTO THU NIGHT. A MIX OF RAIN SHOWERS AND SNOW SHOWERS MAY BE SEEN...MAINLY EARLY THU MORNING AND FRIDAY NIGHT. AT THIS TIME...HAVE RESTRICTED MENTION OF SLIGHT CHANCE RAIN/SNOW SHOWERS TO SATURDAY NIGHT IN LATER PERIODS OF EXTENDED. HIGHS START OUT IN THE 50S WED AND LOWS THU IN THE 40S WITH A GENERAL COOLING TREND THROUGH THE REMAINDER OF THE EXTENDED PERIOD. EXPECT HIGHS FOR THE MOST PART IN THE 40S AND LOWS IN THE 30S. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION... NATIONAL WEATHER SERVICE TALLAHASSEE FL 315 PM EST MON NOV 13 2006 .SYNOPSIS... 18Z WATER VAPOR AND RUC ANALYSIS CONTINUES TO SHOW THE CLOSED UPPER LOW THAT AFFECTED THE MID-ATLANTIC AND SOUTHEASTERN STATES THIS PAST WEEKEND PULLING WELL OFF THE ATLANTIC COAST TO THE SOUTH OF NEW ENGLAND. BEHIND THIS SYSTEM BRIEF UPPER RIDGING BRIEFLY MOVED ACROSS THE SOUTHEASTERN CONUS BUT HAS ALREADY BEGUN TO HEAD OFF TO THE EAST. FURTHER UPSTREAM A SERIES OF DISTURBANCES ARE SEEN IN THE FLOW...WITH ONE SHARP UPPER TROUGH MOVING THROUGH THE MISSISSIPPI VALLEY...AND ANOTHER WEAKER SYSTEM MOVING INTO THE INTERMOUNTAIN WEST. EVEN FURTHER BACK...ONE MORE PIECE OF ENERGY OFF THE PACIFIC NORTHWEST COAST WILL BE COMING ASHORE THIS EVENING AND OVERNIGHT. THIS ENERGY WILL EVOLVE OVER THE NEXT 60 HOURS INTO A STRONG AND DYNAMIC SYSTEM ACROSS THE LOWER AND CENTRAL MISSISSIPPI VALLEY... THEN LIKELY BECOME OUR NEXT SIGNIFICANT WEATHER EVENT BY WEDNESDAY AFTERNOON OR EVENING AS THE SYSTEM AND ASSOCIATED STRONG COLD FRONT RAPIDLY PUSHES EAST. AT THE SURFACE WE SEE HIGH PRESSURE CENTERED OFF TO THE NORTH AND WEST OF THE FORECAST AREA. A WEAK COLD FRONT IS ALSO CURRENTLY PUSHING INTO THE MISSISSIPPI VALLEY ASSOCIATED WITH THE SHORTWAVE MENTIONED ABOVE. THIS FRONT WILL ESSENTIALLY WASH OUT OVER THE NEXT 12 HOURS WITH LITTLE TO NO IMPACT ON OUR AREA. && .SHORT TERM (TONIGHT THROUGH THURSDAY)... WEAK MID-LEVEL SHORTWAVE WILL MOVE INTO THE SOUTHEASTERN STATES DURING THE EVENING HOURS REACHING THE MID-ATLANTIC BY TUESDAY MORNING. THE ATMOSPHERIC COLUMN IS FAR DRY ENOUGH TO PREVENT ANY QPF SO DRY CONDITIONS WILL HOLD THROUGH THE OVERNIGHT. THERE WILL BE HOWEVER JUST ENOUGH MID-HIGH LEVEL MOISTURE ADVECTION COMBINED WITH A BROAD AREA OF 500-300MB Q-VECTOR CONVERGENCE AND 300-200MB DIFFLUENCE TO RESULT IN AT LEAST SOME INCREASE IN CLOUDS FOR THE EVENING AND OVERNIGHT HOURS. REALLY THE ONLY IMPACT OF THESE CLOUDS WILL BE TO HELP KEEP TEMPERATURES UP A FEW DEGREES FROM LOWS LAST NIGHT. ANOTHER VERY WEAK ROUND OF SHORTWAVE ENERGY WILL CROSS THE FORECAST AREA DURING THE DAY ON TUESDAY. ONCE AGAIN ONLY EXPECTING A SLIGHT INCREASE IN CLOUDS WITH THIS SYSTEM...THE MOST COVERAGE SHOULD BE OVER OUR AL/GA ZONES. REGARDLESS...WILL BE GOING WITH GENERALLY PARTLY CLOUDY CONDITIONS FOR ALL ZONES. UPPER LEVEL ENERGY BEGINS TO REALLY CONSOLIDATE OVER THE CENTRAL AND SOUTHERN PLAINS TUESDAY NIGHT WITH THE ENERGY CLOSING OFF NEAR WESTERN ARKANSAS BY SUNRISE WEDNESDAY. SURFACE LOW OVER THE WESTERN PLAINS TUESDAY EVENING WILL EJECT EASTWARD TO NEAR CENTRAL ARKANSAS BY WEDNESDAY MORNING WHILE DEEPENING RAPIDLY. DURING THIS TIME-FRAME...OUR AREA WILL BEGIN TO SEE SIGNIFICANT MOISTURE RETURN DEVELOPING FROM THE SOUTH AND SOUTHEAST. WEDNESDAY MORNING IS LIKELY TO SEE A STRONG COLD-FRONT TRAILING FROM THE LOW OVER THE WESTERN TENNESSEE VALLEY BACK THROUGH LOUISIANA AND INTO THE WESTERN GOMEX. LIKELY TO SEE AN ONGOING PRE-FRONTAL SQUALL LINE OVER THE LOWER MISSISSIPPI VALLEY THAT WILL MAKE PROGRESS DURING THE DAY TOWARD OUR WESTERN FL/AL ZONES. ALTHOUGH THE FINER DETAILS WILL BECOME CLEARER OVER THE NEXT 24-36 HOURS...THE SYNOPTIC PATTERN IS VERY SIMILAR BETWEEN THE NAM/GFS/ECMWF/UKMET FOR SYSTEM EVOLUTION. NAM/GFS BOTH AGREE ON BRING THE COLD-FRONT/SQUALL LINE INTO OUR AL/PANHANDLE ZONES LATE AFTERNOON OR EARLY EVENING ON WEDNESDAY...AND THEN CROSSING OUR GA/BIG BEND COUNTIES DURING THE EVENING AND FIRST PART OF THE NIGHT. AT THIS TIME THE POTENTIAL DOES EXIST FOR SOME OF THE STORMS TO BE STRONG TO SEVERE FROM MID-AFTERNOON THROUGH THE EVENING HOURS. SPC HAS OUTLINED OUR AREA FOR A SLIGHT RISK DURING THIS TIME. IN THE PRE-FRONTAL ENVIRONMENT GUIDANCE SHOWING IMPRESSIVE UNI-DIRECTION 0-6KM BULK SHEAR VALUES OF 50-55 KNOTS ACROSS MUCH OF OUR AREA...INCLUDING A NEAR 50 KNOT 850MB JET. LARGE SCALE FORCING FOR ASCENT IS ALSO SEEN WITH DEEP LAYER Q-VECTOR CONVERGENCE AND STRONGLY DIFFLUENT FLOW IN THE UPPER LEVELS. AT THIS TIME THE MAIN CONCERN WILL BE FOR DAMAGING WIND POTENTIAL. COLD-FRONT SHOULD THEN BE MOVING THROUGH CENTRAL FLORIDA TOWARD SUNRISE ON THURSDAY MORNING. DESPITE A GENERALLY DRY DAY EXPECTED BEHIND THE FRONT. PLENTY OF MID/UPPER LEVEL ENERGY AND MOISTURE ASSOCIATED WITH THE DEEP TROUGH OVER THE EASTERN U.S. WILL RESULT TO PARTLY TO MOSTLY CLOUDY CONDITIONS FOR AT LEAST THE FIRST PART OF THE DAY WITH CLEARING MORE LIKELY WAITING UNTIL THE OVERNIGHT HOURS. && .LONG TERM (THURSDAY NIGHT THROUGH MONDAY)... SURFACE HIGH PRESSURE BUILDS IN LATE THURSDAY AND SETTLES OVER THE LOCAL AREA FRIDAY THROUGH EARLY SATURDAY. THEN A RE-ENFORCING AREA OF HIGH PRESSURE BUILDS DOWN FROM THE NORTHWEST LATE SATURDAY INTO SUNDAY USHERING IN WHAT COULD BE OUR COLDEST AIRMASS THIS FALL SEASON. MAX TEMPS SUNDAY MAY ONLY BE IN THE UPPER 50S FOR MOST OF OUR AL AND GA ZONES AND BY DAYBREAK MONDAY WE MAY SEE OUR FIRST WIDESPREAD FREEZE. && .MARINE... HIGH PRESSURE BUILDS ACROSS THE COASTAL WATERS THROUGH TUESDAY MORNING. THIS HIGH WILL THEN MOVE EAST TUESDAY AFTERNOON AND EVENING AS LOW PRESSURE DEVELOPS ACROSS THE LOWER MISSISSIPPI VALLEY. SOUTHERLY FLOW WILL BEGIN TO STRENGTHEN TUESDAY EVENING AHEAD OF A STRONG COLD FRONT EXPECTED TO APPROACH FROM THE WEST DURING WEDNESDAY. WINDS AND SEAS ARE EXPECTED TO INCREASE TO SMALL CRAFT ADVISORY CRITERIA ACROSS BOTH THE COASTAL AND OFFSHORE WATERS BY WEDNESDAY AFTERNOON AHEAD OF THIS FRONT. THE COLD FRONT IS EXPECTED TO CROSS THE WATERS FROM WEST TO EAST WEDNESDAY EVENING AND NIGHT WITH A ROUND OF SHOWERS AND THUNDERSTORMS. WINDS ARE EXPECTED TO SHIFT TO WEST AND NORTHWEST BY THURSDAY MORNING WITH WINDS AND SEAS FALLING TO EXERCISE CAUTION CRITERIA DURING THE DAY. EXPECT HIGH PRESSURE TO BUILD BACK ACROSS THE WATERS FOR FRIDAY. && .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE ENTIRE TAF PERIOD. MID AND HIGH CLOUDS...AT OR ABOVE 12 KFT...WILL BEGIN TO MOVE INTO THE AREA FROM WEST TO EAST STARTING LATER TODAY...WITH WINDS GENERALLY WEST AROUND 5 KTS. WINDS WILL CALM OVERNIGHT...BUT EARLY MORNING FOG IS NOT EXPECTED AT THIS TIME. FOR TOMORROW... EXPECTING CONDITIONS SIMILAR TO TODAY WITH SCT CLOUDS AROUND 25 KFT AND WINDS AROUND 5 KT. && .FIRE WEATHER... A HIGH PRESSURE RIDGE HAS MOVED OVER THE LOCAL AREA BRINGING COOLER AND MUCH DRIER AIR TO THE REGION. THE AIRMASS WILL SLOWLY BEGIN TO MOISTEN ON TUESDAY. HOWEVER...FOUR HOUR DURATIONS OF RELATIVE HUMIDITY VALUES AT OR BELOW 35 PERCENT ARE STILL EXPECTED DURING THE AFTERNOON HOURS IN PORTIONS OF THE FLORIDA BIG BEND AND PANHANDLE. BY WEDNESDAY...THE AIRMASS WILL BE MOIST ENOUGH TO PRECLUDE RED FLAG CONDITIONS AS THE NEXT FRONTAL SYSTEM APPROACHES FROM THE WEST. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 39 74 50 77 / 0 0 10 50 PANAMA CITY 48 73 58 76 / 0 0 10 70 DOTHAN 42 72 53 73 / 0 0 20 80 ALBANY 39 72 49 75 / 0 0 10 60 VALDOSTA 40 74 48 77 / 0 0 10 30 CROSS CITY 40 75 49 78 / 0 0 10 20 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...RED FLAG WARNING UNTIL 6 PM MONDAY FOR THE FOLLOWING ZONES: CALHOUN...DIXIE...GADSDEN...HOLMES...INLAND WALTON...JACKSON...JEFFERSON...LAFAYETTE...LEON...LIBERTY... MADISON...TAYLOR...WAKULLA...AND WASHINGTON. RED FLAG WARNING FOR TUESDAY FROM 1 PM EST TO 5 PM EST FOR JACKSON...GADSDEN...LEON...JEFFERSON...MADISON...TAYLOR... LAFAYETTE AND DIXIE COUNTIES IN THE FLORIDA BIG BEND. .GM...NONE && $$ AVIATION/FIRE WEATHER...JAMSKI PUBLIC/MARINE...MROCZKA LONG TERM...BARRY fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 310 PM EST MON NOV 13 2006 .SHORT TERM (TONIGHT-TUESDAY)... BAND OF MAINLY MID-LEVEL CLOUDS MOVING THRU THE LMK CWA ATTM...ASSOC WITH APPROACHING 500MB SHORTWAVE TROF. LOW LEVELS ARE FAIRLY DRY ATTM THEREFORE ANY PRECIP ASSOC WITH THESE CLOUDS SHOULD BE LIGHT BUT WILL INCLUDE ISLTD -SHRA THROUGH LATE AFTN...AND A CHANCE OF SPRINKLES INTO THE EVE HOURS. EXPECTING THESE CLOUDS TO EXIT ERN SECTIONS OF THE CWA AFTER 6Z...PER LATEST NAM FCST SOUNDINGS. GFS/NAM ARE SHOWING SOME LOW CLOUDS DEVELOPING/MOVING INTO SRN IND OVERNIGHT AS WELL...BUT MOST OF THE CWA SHOULD BE CLR AFTER 6Z WHICH WITH LIGHT WINDS COULD LEAD TO A FOG SETUP. NAM IS SHOWING INCREASING MOISTURE IN THE BOUNDARY LAYER...ESPECIALLY OVER THE WRN 2/3 OF THE DISTRICT...WHICH WOULD ENHANCE THE FOG THREAT. LATEST RUC IS PAINTING WIDESPREAD M1/4SM VSBYS BY 9Z/TUE...AND MOS DOES SHOW A COMBINATION OF FOG/LOW STRATUS DURING THIS PERIOD AS WELL. WILL MENTION AREAS OF FOG IN THE FCST FOR NOW...I AM NOT CONFIDENT ENOUGH TO ISSUE AN ADVISORY AT THIS TIME BUT THIS WILL HAVE TO BE WATCHED BY LATER SHIFTS. BASED ON CURRENT T-TD SPREADS...FEEL THE WRN CWA WOULD HAVE HIGHEST RISK OF DENSE FOG GIVEN THAT IT'S BEEN CLOUDY THERE MOST OF TODAY. WILL ISSUE AN SPS TO HIGHLIGHT POTENTIAL THREAT. INTO TUESDAY...IF WE DO END UP WITH WIDESPREAD FOG THEN IT MAY TAKE UNTIL MID-MORNING TO CLEAR...WHEN FCST SOUNDINGS INDICATE THAT BOUNDARY LAYER MIXING COMMENCES IN ERNEST. SECOND UPPER LEVEL WAVE IS EXPECTED TO TRAVERSE THE REGION TOMORROW...THE MAIN EFFECT OF THIS WILL LIKELY BE SCT-BKN MID/HIGH LEVEL CLOUDINESS. THERMAL TROF AXIS FCST TO BE OVER THE REGION THOUGH 850MB TEMPERATURE READINGS ARE WITHIN 1 STD DEV OF NORMAL. HAVE USED A BLEND OF GFS/NAM MOS FOR HIGHS TOMORROW...YIELDING LOW 50S NORTH TO NEAR 60 SOUTH. CS .LONG TERM (TUESDAY NIGHT-MONDAY)... DID NOT MAKE TOO MANY CHANGES TO THE EXTENDED FORECAST. CHALLENGES REVOLVE AROUND PRECIP TIMING/AMOUNT WITH MID-WEEK SYSTEM...AND RESULTING TEMPS. TUESDAY NIGHT - FRIDAY NIGHT... FAIRLY GOOD MODEL AGREEMENT WITH THE MID-WEEK STORM SYSTEM. GFS/NAM AND SREF INDICATE THAT A LEE SFC LOW WILL DEVELOP ACROSS THE SRN PLAINS TUESDAY NIGHT AND MOVE SLOWLY TO THE NORTHEAST AS UPPER JET DIGS OUT THIS SYSTEM. THIS BECOMES A NEAR 990MB SFC LOW BY WED MORN SOMEWHERE NEAR THE AR/MO STATE LINE. NAM TAKES A MORE NORTHERN ROUTE AND THUS INDICATES A MORE FAVORABLE SCENARIO FOR T-STORM DEVELOPMENT. GFS TAKES A SLIGHTLY MORE SOUTHERN ROUTE...AND SURFACE AND ELEVATED LI'S REFLECT THE LACK OF INSTABILITY WITH THIS MODEL. WITH GOOD MOISTURE RETURN...COULD SEE RAIN AS EARLY AS LATE TUESDAY NIGHT AND WILL RAMP UP QUICKLY MORE THAN LIKELY. HOWEVER...WILL ONLY HAVE ISLD T-STORM WORDING AS NAM TENDS TO OVERDUE INSTABILITY...AND THE FACT THAT THE EURO ALSO SHOWS THE MORE SOUTHERLY SFC LOW TRACK. HAVE LIKELY POPS IN THE SWRN CWA AFTER MIDNIGHT TUESDAY...AND HAVE CATEGORICAL FOR WEDNESDAY. MAY HAVE HEAVY RAIN AT TIMES...BUT WILL NOT HIGHLIGHT THIS QUITE YET IN THE HWO SINCE IT MAY BE MORE OF A STEADY RAINFALL EVENT. THE CWA WILL BE ON THE BACK SIDE OF THE SFC LOW BY THURSDAY MORNING AS IT MOVES INTO OHIO. IT APPEARS THAT BL TEMPS WILL BE TOO WARM FOR ANYTHING OTHER THAN RAIN...BUT IT WILL BE A COLD RAIN FOR SURE. ANY PRECIP WILL LIKELY MOVE ON OUTTA HERE BY FRIDAY MORNING...AND ACTUALLY TEMPS WILL NOT DROP OFF TOO MUCH BEHIND IT. HOWEVER...IT WILL BE A CLOUDY/DREARY WEEK FOR THE MOST PART. WILL TREND TEMPS TOWARD THE COOLER ENSEMBLE NUMBERS...SIMILAR TO WHAT PREVIOUS FORECASTER ALREADY HAD. SATURDAY-MONDAY... ONLY MADE A MINOR CHANGE TO THIS PERIOD AND ADDED IN SLT CHC POPS FOR SUNDAY. AFTER A BREAK FROM PRECIP ON SATURDAY...FAIRLY STRONG UPPER-LEVEL TROUGH EMBEDDED IN THE NRN STREAM FLOW WILL DIVE DOWN ACROSS THE GREAT LAKES LATE SATURDAY NIGHT. THOUGH THERE WILL NOT BE STRONG RETURN FLOW...THE STRENGTH OF THIS SHORTWAVE COULD GENERATE ISLD SHOWERS DESPITE DRY ATMOSPHERE ON SUNDAY. DEPENDING ON THE TIMING...THESE COULD BE RAIN OR SNOW SHOWERS. PBL TEMPS SHOULD BE WARM ENOUGH DURING THE DAY TIME HOURS TO YIELD RAIN...BUT THICKNESSES ALOFT SUGGEST THAT OVERNIGHT/EARLY MORNING TIME FRAME COULD BE A MIX OR EVEN JUST SNOW SHOWERS. THIS FAR OUT...ONLY INSERTED A SLT CHC...BUT WENT AHEAD AND MENTIONED THE MIX DURING THE COLDEST TIMES SUNDAY MORNING AND LATE SUNDAY NIGHT. EVEN IF SNOW OCCURRED...WOULD NOT ACCUMULATE AT ALL. BEHIND THIS...THE NEXT WEEK LOOKS LIKE A NICE WARM-UP AS RIDGING TAKES PLACE ACROSS THE WRN CONUS. COULD SEE ABOVE AVERAGE TEMPS BY THANKSGIVING IF THE TREND STAYS THE SAME. AL && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 256 PM EST MON NOV 13 2006 .DISCUSSION... TONIGHT THROUGH WEDNESDAY NIGHT... LOW STRATUS DECK HAS BEEN SLOWLY PULLING OFF TO THE NORTHEAST. AT THE SAME TIME MID LEVEL DECK ASSOCIATED WITH 500 MB TROF IS ADVANCING SLOWLY EAST FROM WESTERN KY. AT CURRENT MOVEMENT...CLOUD DECK WILL MOVE INTO WESTERN PART OF FORECAST AREA AROUND 00Z. THIS IS IN GOOD AGREEMENT WITH THE 12Z GFS. EXPECT THIS TO MOVE EAST OF FORECAST AREA BY 08Z. EXPECT CLOUDS TO PREVENT WIDESPREAD FOG AND LOW CLOUD DEVELOPMENT TONIGHT...BUT THIS WILL NEED TO BE MONITORED ESPECIALLY IN WESTERN PART OF FORECAST AREA. ANOTHER WEAK SHORT WAVE TROF TO MOVE ACROSS OH VALLEY ON TUESDAY..WITH MAIN AFFECT SOME INCREASED CLOUDINESS NORTH AND WEST OF FORECAST AREA. MAIN FOCUS SHIFTS TO DEEPENING MID AND UPPER LEVEL TROF MOVING EAST THEN CUT OFF 5H LOW INTO MID MS VALLEY BY 00Z THURSDAY. THERE IS GENERAL AGREEMENT BETWEEN THE GFS AND NAM-WRF WITH 12Z NAM SHOWING 5340 500 MB LOW INTO FAR WEST KY BY 00Z THURSDAY...AND WRF SHOWING A 5370 500 MB LOW OVER FAR WEST TN AT SAME TIME. BOTH MODELS DEVELOP A SIGNIFICANT SURFACE LOW OF 989 TO 990 MB BY 00Z THURSDAY WITH WRF FURTHER NORTH IN AGREEMEENT WITH IT/S FORECAST UPPER AIR PATTERN. WITH ONLY MINOR DIFFERENCES...AND BOTH MAV MOS AND MET MOS PAINTING 90 TO 100 POPS FOR WEDNESDAY AND WEDNESDAY NIGHT...HAVE UPPED POPS TO 100 PERCENT FOR THIS TIME FRAME. EVEN THOUGH SURFACE INSTABILITY WILL BE EXTREMELY LIMITED HAVE CONTINUED SLIGHT CHANCE OF THUNDER IN GRIDS WITH STRONG DYNAMICS AND LIFT. AS FOR TEMPERATURES...CLOUDS SHOULD PREVENT SIGNIFICANT RIDGE VALLEY SPLIT TONIGHT...BUT SHOULD SEE ENOUGH CLEARING EARLY AND AGAIN AFTER 07Z FOR A 5 DEGREE SPLIT TO DEVELOP. THIS IS ALSO HINTED AT BY MOS GUIDANCE. NO SIGNIFACNT DIFFERENCES IN MOS TEMPERATURE GUIDANCE UNTIL WEDNESDAY AND WEDNESDAY NIGHT. WITH WIDESPREAD SHOWERS EXPECTED WEDNESDAY HAVE FOLLOWED COOLER MAV MOS GUIDANCE FOR HIGHS. FOR WEDNESDAY NIGHT HAVE TRENDED LOWER THAN MAV MOS WITH GOOD CAA SETTING UP BY 06Z THURSDAY. THURSDAY THROUGH MONDAY... EXTENDED PERIOD BEGINS WITH A DEEP CUT OFF LOW PRESSURE AREA CENTERED OVER THE BLUEGRASS STATE. THE LOW WILL SLOWLY LIFT NORTH INTO CANADA BY SATURDAY...HOWEVER MODELS INDICATE THE UPPER LEVEL TROUGH OVER THE EASTERN CONUS WILL BE REINFORCED LATE IN THE WEEKEND AND FOR THE FIRST PART OF THE WORK WEEK. THE VARIOUS LONG RANGE MODELS ARE IN GOOD AGREEMENT ON THE OVERALL FORECAST PATTERN FOR EASTERN KENTUCKY...THEREFORE CONFIDENCE LEVEL IS FAIRLY HIGH IN A CHILLY AND RATHER UNSETTLED WEATHER PATTERN CONTINUING INTO THE FIRST PART OF THE NEW WORK WEEK. WRAP-AROUND MOISTURE AND COLD AIR ADVECTION WILL PLAGUE THE FORECAST AREA ON THURSDAY AS THE SURFACE LOW WORKS BY JUST TO OUR NORTH AND EAST. WHILE H850 TEMPS ARE SHOWN TO DROP BELOW ZERO BY DAY/S END...LOW-LEVEL THICKNESSES DON/T SUPPORT SNOWFALL. THE CHILLY SHOWERS SHOULD GRADUALLY TAPER OFF THURSDAY NIGHT AS THE LOW LIFTS OFF TO THE NORTHEAST...WITH CLOUDS GRADUALLY DECREASING ON FRIDAY. SEVERAL IMPULSES ARE PROGGED TO DIVE SOUTHEAST INTO THE OHIO VALLEY AND SOUTHERN APPALACHIANS SATURDAY NIGHT THROUGH MONDAY BRINGING ANOTHER CHANCE FOR SOME RAIN AND SNOW SHOWER ACTIVITY WITH MUCH BELOW NORMAL TEMPS. && .PREV DISCUSSION... 1019 AM EST MON NOV 13 2006 CHALLENGE FOR THE DAY IS THE PERSISTENT STRATUS DECK THAT COVERS EASTERN KY. VISIBLE SATELLITE SHOWS HIGHER MOUNTAINS IN LETCHER...HARLAN...AND BELL COUNTY EXTENDING ABOVE THE CLOUDS. THIS IS ALSO VERIFIED WITH WEB CAM ON MOUNTAINS NEAR MIDDLESBORO. CEILINGS ARE GENERALLY BELOW 1000 FEET...AND BASED ON 12Z SOUNDINGS...AND OBSERVATIONS NOTED ABOVE...THE CLOUDS ARE ONLY ABOUT 1000 FEET THICK. WITH VERY STRONG INVERSION PRESENT AND FORECAST TO PERSIST THE CLOUDS WILL BE VERY SLOW TO BREAK UP...EVEN THOUGH THEY ARE SHALLOW IN DEPTH. THE 12Z NAM AND LATEST RUC DO NOT HAVE A GOOD HANDLE ON THE MOISTURE AT 925 MB...BUT NAM LOOKS BEST AND INDICATES LITTLE CHANGE IN MOISTURE PATTERN UNTIL MID AFTERNOON. WITH ALL THIS IN MIND WILL UPDATE GRIDS AND ASSOCIATED FORECAST PRODUCTS TO ACCOUNT FOR MORE CLOUDS INTO THE AFTERNOON. PREVIOUS FORECAST HAD ALREADY LOWERD MAX TEMPS FROM GUIDANCE. THE 12Z MET AND FWC FORECAST MOS TEMPS FOR THIS AFTERNOON STILL LOOK TOO HIGH. HAVE LOWERED MAX TEMPERATURE FORECAST A FEW MORE DEGREES. 559 AM EST MON NOV 13 2006 PERSISTENT STRATOCU HAVE BEEN VERY SLOW TO SCATTER OUT OVERNIGHT IN THE FAR SW COUNTIES AND HANGS ON OVER THE REST OF THE CWA. SME AND EKQ HAVE GONE CLEAR...WHILE 1A6 DID FOR A TIME...BUT SC ADVECTED BACK TO THE WEST ON THE E TO ESE FLOW BETWEEN THE WEAKENING RIDGE OF HIGH PRESSURE AND A TROUGH EXTENDING THROUGH THE PLAINS. THE CLEARING IS NEAR LOZ...BUT CLOUDS HAVE ADVECTED BACK TO THE WEST THERE. IN ADDITION...THE SOUTHERN EXTENT OF THE STRATOCU IN NE TN ALSO SEEMS TO BE ADVANCING TO THE NORTH. THE WESTERN EDGE OF THE STRATOCU IS ABOUT 25 MILES WEST OF I 65. HOWEVER...HIGH AND SOME MID CLOUDS WERE WORKING EAST ACROSS THE MS VALLEY AND INTO THE OH VALLEY IN ADVANCE OF A SW/V TROUGH ASSOCIATED WITH THE ABOVE MENTIONED SFC TROUGH. THE MAIN WEATHER MAKER FOR THIS FORECAST IS THE SYSTEM WORKING ONTO THE WEST COAST ATTM. THE BIGGEST FORECAST CHALLENGE EARLY IN THE PERIOD IS THE EROSION OF THE STRATOCU TRAPPED BELOW THE SUBSIDENCE INVERSION. THE RELATIVELY WEAK NOVEMBER SUNSHINE SHOULD BE SLOW TO HELP ERODE THESE CLOUDS AWAY TODAY...WHEN COMBINED WITH THE HIGH AND MID CLOUDS WORKING IN. THE CLEARING IN THE SW COUNTIES OVERNIGHT IS PROMISING AND IN GENERAL...EXPECT SOME GRADUAL CLEARING FROM SW TO NE THROUGHOUT THE DAY THOUGH FAIRLY DENSE CIRRUS AND SOME OCCASIONAL AC SHOULD WORK ACROSS THE REGION TODAY. CLEARING OF THE SC MAY NOT REACH THE FAR EASTERN AND NE COUNTIES UNTIL THE 18 TO 21Z TIME FRAME. THE SC COMBINED WITH THE SIGNIFICANT HIGH AND SOME MID CLOUDS WILL HOLD BACK TEMPS SUBSTANTIALLY AND HAVE UNDERCUT MAV NUMBERS BY SEVERAL DEGREES ACROSS THE BOARD AS THE GFS APPEARS TO HAVE A POOR HANDLE ON THE SC. OPTED TO GO MORE IN LINE WITH A COMPROMISE BETWEEN THE COOLER FWC/MAV NUMBERS. WEAKENING SFC HIGH PRESSURE WITH SW/V RIDGING WORKING INTO THE REGION LATER TONIGHT SHOULD LEAD TO CLEAR SKIES AND LIGHT WINDS. A SMALL RIDGE/VALLEY TEMPERATURE SPLIT APPEARS IN STORE WITH RELATIVELY DRY AIR IN PLACE...DEWPOINTS EXPECTED TO BE IN THE LOWER 30S...AND GOOD RADIATIONAL COOLING CONDITIONS ESPECIALLY DURING THE SECOND HALF OF THE NIGHT. VALLEY LOCATIONS SHOULD DECOUPLE AND COOL INTO THE LOWER 30S...WITH RIDGETOPS HOLDING IN THE UPPER 30S. MODERATING TEMPERATURES ARE EXPECTED ON TUESDAY WITH MORE SUNSHINE OVERALL THAN TODAY...WITH WEAK SFC RIDGING IN PLACE. THE MAIN WEATHER MAKER FOR THIS FORECAST PERIOD IS EXPECTED TO BEGIN TO REALLY TAKE SHAPE TO THE LEE OF THE ROCKIES ON TUESDAY AFTERNOON. A SW/V THAT SHOULD ENTER THE PACIFIC NW LATER TODAY...AND MOVE THROUGH THE ROCKIES IS EXPECTED TO DEEPEN THE EASTWARD MOVING MID LEVEL SW/V AND HELP CLOSE OFF A MID LEVEL LOW OVER THE SOUTHERN PLAINS ON TUESDAY NIGHT. AT THE SAME TIME THE SFC LOW SHOULD REORGANIZE OVER THE OK/AR AREA AND THEN TRACK NE TO OZARKS/SW MO AREA BY 12Z ON WED. PRECIPITATION ON ISENTROPIC LIFT SHOULD OVERSPREAD MIDDLE TN AND THE CUMBERLAND PLATEAU AND THREATEN AREAS TO THE WEST OF I 75 BY AROUND SUNRISE ON WED IN ADVANCE OF THIS SYSTEM. AN AREA OF RELATIVELY STRONG ISENTROPIC LIFT SHOULD REACH THE NE COUNTIES BY WED AFTERNOON AS THE WARM FRONT LIFTS N INTO THE REGION. GFS/NAM AND 13/21Z SREF ARE CONSISTANT IN BRINGING THE PRECIPITATION ACROSS THE REGION ON WED AND THEN WED NIGHT AS THE COLD FRONT CROSSES THE AREA. OPTED TO RAISE POPS HIGHER...INTO THE CAT RANGE ON WED AND WED NIGHT. 0Z MET WAS INTO THE CAT RANGE FOR WED...WITH THE 6Z MAV NOW CAT ON WED. 12 HOUR MEX POPS FOR WED NIGHT WERE CAT AS WELL. OVERALL...QPF FOR THE EVENT SHOULD BE IN THE 0.50 TO 0.80" RANGE...BRINGING BENEFITIAL RAIN AND HELPING TO KEEP FOREST FUELS MOIST. EXTENDED...OVERALL THE EXTENDED FORECAST WAS IN GOOD SHAPE AND MADE LITTLE IF ANY ADJUSTMENTS. OPTED TO RAISE POPS IN THE N ON THU (AREA THAT WILL BE CLOSEST TO THE MID LEVEL LOW CENTER TO THE LIKELY RANGE FOR THU. OTHERWISE...INCLUDED THE CHANCE FOR SOME SNOW SHOWERS ON THU NIGHT ACROSS THE HIGHEST ELEVATIONS NEAR THE TN LINE AS GFS/ECMWF FORECAST SUB 0C 8H TEMPS. 911 PM EST SUN NOV 12 2006 AREA OF SURFACE HIGH PRESSURE IS CURRENTLY NOSED IN ACROSS THE OHIO VALLEY FROM THE NORTH. STRATOCUMULUS DECK HAS BEEN A JUGGERNAUT AS MOISTURE REMAINS TRAPPED BELOW A VERY POTENT INVERSION BETWEEN 925 AND 850 MB. IN FACT...SATELLITE TRENDS OVER THE PAST FEW HOURS HAVE SHOWN A SLIGHT EXPANSION OF THE DECK TO THE WEST. UPPER AIR CHARTS AND VAD WIND PROFILES CONFIRM THE NORTHEAST FLOW IN PLACE AT THE LOW LEVELS. THIS FLOW PATTERN IS PROGGED TO HOLD TRUE FOR THE REST OF THE NIGHT. AS SUCH...WILL KEEP CLOUDY SKIES ACROSS THE AREA FOR THE REST OF THE NIGHT AND INTO EARLY TOMORROW MORNING. CONSEQUENTLY...WILL REMOVE THE MENTION OF FOG...INCREASE LOW TEMPERATURES TO THE MID 30S TONIGHT AND INCLUDE SOME LOWER RANGED NUMBERS FOR TOMORROWS HIGHS...PARTICULARLY IN THE EAST...WHERE A CLEAR START IS UNLIKELY. UPDATE OUT BEFORE TOO LONG. 524 PM EST SUN NOV 12 2006 SATELLITE TRENDS ARE A BIT SLOWER WITH THE CLEARING OVER THE PAST HOUR OR SO. AS SUCH...WILL UPDATE TO MENTION MOSTLY CLOUDY TO CLOUDY SKIES EARLY IN THE EVENING. WILL REASSESS CLEARING AND FOG POTENTIAL AS WELL AS LOW TEMPERATURES A BIT LATER. UPDATE OUT SHORTLY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SBH/ABE ky AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LOUISVILLE KY 1234 PM EST MON NOV 13 2006 .UPDATE... CLEAR AREA HAS DEVELOPED MORE THAN EARLIER ANTICIPATED FROM LEX DOWN INTO SRN KY. HOWEVER AM EXPECTING THAT SKIES WILL BECOME PARTLY SUNNY TOWARD MID/LATE AFTERNOON AS MID LEVEL CLOUDS ADVANCE FROM THE WEST...THEREFORE HAVE AMENDED ONLY THE GRIDDED FORECAST AT THIS TIME TO INCLUDE A MOSTLY SUNNY PERIOD FOR THE NEXT FEW HOURS. CS && .PREV DISCUSSION... (ISSUED 1031 AM EST MON NOV 13 2006) UPDATE... LATE MORNING UPDATE WILL PRIMARILY FOCUS ON LOWERING FCST HIGHS FOR TODAY. SCT-BKN LOW CIGS CONTINUE OVER MUCH OF THE NRN 2/3 OF THE CWA. IN ADDITION...BKN-OVC MID LEVEL CLOUDS IN ASSOC WITH APPROACHING UPPER WAVE ARE MOVING INTO THE CWA FROM THE WEST. LATEST RUC LOW LEVEL RH DATA KEEPS THESE CLOUDS IN THROUGH AT LEAST 18Z...VERY STRONG 925MB INVERSION SEEN IN 14Z ACARS SOUNDINGS AT SDF WILL HELP MAINTAIN THEM. HOWEVER WE ARE SEEING A NUMBER OF BREAKS IN THE LOW CIGS (W OF SDF AND IN THE BLUEGRASS) IN LATEST SATELLITE PIX...BUT WILL STILL LOWER FCST HIGHS GIVEN THE SLOW START WE'VE HAD TODAY. RECENT MODELS ARE CONSISTENT IN DISSIPATING PCPN CURRENTLY RUNNING FROM EVV-PAH BEFORE IT GETS INTO OUR DISTRICT. HOWEVER WOULD NOT BE SURPRISED TO SEE SOME SPRINKLES IN OUR FAR W/NW ZONES SO WILL ADD THAT TO THE FCST. AIRMASS IS QUITE DRY OVER THE LMK CWA...SO EASTWARD EXTENT OF ANY PCPN IS QUESTIONABLE. WILL HAVE TO WATCH SHRA DEVELOPING OVER WRN TN AS THEY LIFT OFF TO THE NE. REST OF FCST UNCHANGED AT THIS TIME. UPDATE OUT BY 11 AM EST. CS PREV DISCUSSION... (ISSUED 737 AM EST MON NOV 13 2006) UPDATE... SENDING OUT A QUICK UPDATE TO ACCOUNT FOR EXTENSIVE LOW CLOUDS OVER MUCH OF THE LMK CWA AS OF 1230Z. FOLLOWING LATEST RUC...WHICH HAS A DECENT HANDLE ON CURRENT CLOUD DISTRIBUTION...EXPECT SKIES TO REMAIN MOSTLY CLOUDY THIS MORNING. CLOUDS ASSOC WITH UPSTREAM SHORTWAVE MAY KEEP US MOSTLY CLOUDY INTO THE AFTN...WILL EVALUATE THAT WITH THE LATE MORNING UPDATE. CONSENSUS OF MODELS DRIES OUT PCPN CURRENTLY OVER SRN IL/SE MO BEFORE IT REACHES THE LMK CWA...BUT WILL KEEP AN EYE ON IT. UPDATED FCST OUT BY 8 AM EST. CS PREV DISCUSSION... (ISSUED 330 AM EDT MON NOV 13 2006) SHORT TERM (TODAY AND TONIGHT)... MAIN FCST CHALLENGE THIS PERIOD IS CLOUD FCST. STRATOCU IN THE 1 TO 2 FOOT THOUSAND RANGE HAVE CONTD TO SPREAD WNWRD ACRS CENTRAL KY AND SOUTH CENTRAL IN DESPITE MODEL PROGS SHOWING OTHERWISE (SIGNIFICANT RH DECREASE BY 06Z). WINDS AT CLOUD BASE SHUD VEER FROM SE TO SW BY 12UTC...IT APPEARS LO CLOUDS SHUD LIFT TO OUR N IN THE NEXT FEW HRS WITH OVC SKIES CONFINED TO OUR NE SCTNS AFTER SUNRISE. SATELLITE IMAGERY SUPPORTS THIS ATTM WITH OUR 88-D VAD WIND PROFILE SHOWING ESE WINDS AT 15K. BKN CI HAS OVERSPREAD THE LOW CLOUDS ACRS NRN SECTIONS OF OUR FA AND THAT SHUD BE THE DOMINANT CLOUD AT SUNRISE. NETWORK RADARS TO OUR WEST INDICATING SHOWERS ACRS MO AND WRN IL AHEAD OF SHRTWV TROF ACRS THE CENTRAL PLAINS AND ERN KS CDFNT. THAT TROF PROGGED TO WEAKEN AS IT REACHES ERN IL THIS AFTN WITH MS VLY TROF...JUST IN ARREARS...MOVG THRU OUR FA EARLY TNGT. GFS HAS A BETTER HANDLE ON THE SHOWERS SHOWING DEEPER MSTR ACRS MO ATTM. CDFNT BECOMES DIFFUSE THIS EVE...REFLECTING WEAKENING UPR LVL FORCING WITH LITTLE OR NO CONVERGENCE RESULTING IN JUST CLOUD DEBRIS OVERSPREADING OUR AREA DURG THE AFTN AND EVE. BASED ON MODEL CROSS SECTIONS AND SATELLITE IMAGERY...IT APPEARS CI WILL OVERSPREAD OUR FA THIS MRNG...LEAST AMOUNT IN THE SOUTH...FOLLOWED BY MID CLOUDS IN THE AFTN AND SCT-BKN LO CLDS TNGT. SO CURRENT FCST OF FILTERED SUNSHINE TDA AND PARTLY CLDY CONDS TNGT LOOKS FINE WITH NO MENTION OF PRECIP. MOS TEMPS TDA/TNGT CLOSE TO ONGOING FCST...SEE NO REASON TO STRAY. MAY HAVE TO DO A SUNRISE UPDATE...IF LO CLOUDS DONT LIFT TO THE N AS EXPECTED. KIRKPATRICK LONG TERM (TUESDAY THROUGH MONDAY)... TUESDAY AND WEDNESDAY... SIGNIFICANT WEATHER CHALLENGES FOR THE EARLY PORTIONS OF THE LONG TERM...HAVE STAYED CLOSE TO A GFS/NAM BLEND THRU THE PERIOD TO WASH OUT SOME OF THE TRACK DIFFERENCES OF THE STRONG SFC LOW WEDNESDAY. THE SREF MEAN ARE LEANING SLIGHTLY MORE TOWARDS THE NAM TRACK...IF THIS WERE TO VERIFY IT WOULD HAVE SOME POSSIBLE RAMIFICATIONS FOR SEVERE THREAT WITH THE SLIGHTLY MORE NORTHERN TRACK. LITTLE ALTERATION TO THE TEMPS GRIDS FOR THE PERIOD FROM PREVIOUS FORECAST. WEAK SHRTWV MOVING THROUGH THE MID OHIO VALLEY AND GREAT LAKES TUESDAY...SOME SCATTERED TO BROKEN CLOUDS WILL BE POSSIBLE THROUGH THE AFTERNOON. DEVELOPING LOW ACROSS THE SOUTH CENTRAL PLAINS NEAR OKC TUESDAY EVENING WILL START TO MOVE NORTHEAST...INCREASING CLOUDINESS FROM SW TO NE DURING THE OVERNIGHT PERIOD. PRECIP CHANCES LOOKS TO HOLD OFF THROUGH THE NIGHT...WITH A CHANCE MAYBE STILL AROUND THE BWG AREA IN THE EARLY MORNING HOURS. PRECIP LOOKS TO OVERSPREAD THE FORECAST DURING THE MORNING INTO THE LUNCH HOUR. THE GFS HAS A SLIGHTLY FURTHER SOUTH TRACK THAN THE NAM AND SREF...HAVE BLENDED AS MENTIONED BEFORE...WITH THE TRACK GOING FROM NEAR MEM TO JUST NORTH OF CINCY. NAM SUGGESTS SOME DRY SLOTTING POSSIBLE IN THE LATE EVENING INTO THE EARLY MORNING HOURS OF THURSDAY...HAVE ADDED SLIGHTLY LOWER POPS HERE...WITH THE MAJORITY OF THE WRAP AROUND MOISTURE LOOKING TO STAY NEAR OR NORTH OF THE OHIO RIVER...HAVE KEPT HIGHER POPS ACROSS THE NORTH LATE WEDNESDAY NIGHT. RAW MODEL DATA WOULD SUGGEST THAT THE PREVIOUS THINKING OF A MIX IN P-TYPE LOOKS IN JEOPARDY AS THE LOW DOESN'T TAP ANY REALLY COLD AIR...BOUNDARY LAYER TEMPS DON'T GET MUCH BELOW 40 DEGREES AND THE H850 TEMPS ONLY DROP TO -2 OR SO AT THE COLDEST...NOT GOOD CONDITIONS FOR FROZEN PRECIP. MORE IMPORTANTLY IS THE SEVERE THREAT FOR WEDNESDAY...SPC HAS BROUGHT THE SLIGHT RISK REGION JUST TO THE SOUTH OF THE REGION IN MIDDLE TN...IF THE TRACK BECOMES FURTHER NORTH...CLOSER TO THE NAM THEN THIS THREAT AREA COULD BE ADJUSTED TO CONTAIN SOUTHERN KY...THE DYNAMICS OF THIS SYSTEM ARE VERY IMPRESSIVE WITH A STRONG LOW LEVEL JET AND INCREDIBLE SHEAR GENERATED BY THE STRONG WESTERLY COMPONENT OF THE H500 AND H250 JETS. THE ISSUE WILL BE INSTABILITY...IT LOOKS HARD TO COME BY...BUT IF THE NORTHERLY TRACK HITS THEN ENOUGH MAY BE THERE TO MIX DOWN SOME STRONG WINDS...OR WITH THE SIGNIFICANT SHEAR EVEN A TORNADO OR TWO AS LOW TOPPED SUPERCELLS WOULD BE POSSIBLE...THOUGH AS IT STANDS RIGHT NOW THIS SCENARIO IS NOT THE PREFERRED SOLUTION. IT WILL BE IMPORTANT TO WATCH THE DETAILS OF THIS SYSTEM CAREFULLY OVER THE NEXT 48 HOURS. THURSDAY THROUGH MONDAY... OVERALL THE PATTERN THE LAST FEW DAYS HAS ONLY HAD THE TREND OF SOME INCREASED TROUGH ACROSS THE EASTERN THIRD OF THE CONUS FOR NEXT WEEKEND...OTHER THAN THAT A FAIRLY STABLE SET OF SOLUTIONS. THE OPERATIONAL 00Z EURO AND GFS ARE IN PRETTY DECENT AGREEMENT THRU FRIDAY...THEN THEY START TO VEER FROM EACH OTHER BY EARLY NEXT WEEK. THE MORE CONSISTENT OF THE TWO SOLUTIONS FOR NEXT WEEK IS FOUND USING THE GFS AND ITS ENSEMBLE MEAN...AS THE EURO HAS BEEN HAVING SOME ISSUES DEALING WITH THE TROUGH FROM THE WEEKEND AND THEN THE WESTERN ATLANTIC PATTERN AS A WHOLE...THOUGH UNUSUALLY STRONG AGREEMENT FOUND IN THE PACIFIC LATE IN THE PERIOD. WILL BE USING A BLEND OF THE 00Z GFS AND 00Z EURO INTO FRIDAY...THEN MOVING WHOLLY TOWARDS THE VERY STABLE GFS ENSEMBLE SOLUTION FROM LATER FRIDAY INTO EARLY NEXT WEEK. THE EURO IS SLIGHTLY FASTER MOVING THE CLOSED LOW INTO QUEBEC BY LATE THURSDAY AND THEN TOWARDS JAMES BAY BY FRIDAY...CLOUDS LOOK TO FINALLY EXIT THE REGION LATE FRIDAY MORNING AS SFC HI BUILDS ACROSS THE SE CONUS STATES. WARP AROUND PRECIP SHOULD LINGER INTO THURSDAY...ENDING BY THE EARLY EVENING HOURS AND SHOULD BE MORE LIKELY ACROSS THE NORTHERN PORTIONS OF THE FORECAST AREA. COOL AREA OF CANADIAN HI PRESSURE STARTS TO DRIFT SE FROM THE NORTHERN ROCKIES SATURDAY AS A DRY FRONT MOVES ACROSS THE REGION...THOUGH THE OPER GFS SHOWS PRECIP HAVE NOT MENTIONED AS THE ENS MEAN SHOWS THE POPS WELL LESS THAN CLIMO. COOL NORTHERLY FLOW LOOKS TO STICK AROUND SUNDAY AND MONDAY AS CANADIAN HIGH MOVES ACROSS THE CENTRAL PLAINS INTO THE SOUTHERN STATES BY MONDAY. AGAIN THE GFS HINTING AT SOME MOISTURE FROM THE LAKES WORKING SOUTH...COVERAGE WOULD BE REMARKABLY SMALL...AND MORE LIKELY ACROSS E KY AND ENS POPS ARE AGAIN MUCH LOWER THAN CLIMO...WILL LEAVE DRY SUNDAY IN THE EAST AS WELL. SUNNY SKIES LOOK LIKELY. TEMPS SATURDAY THRU MONDAY LOOK TO BE 4 TO 8 DEGREES BELOW NORMAL THROUGH THE PERIOD WITH SOME MORNINGS AT OR BELOW FREEZING. HAVE LEANED MORE TOWARDS THE GFS AND ENS GFS LATER IN THE PERIOD FOR THE CONSISTENCY IT HAS SHOWN THERE...BUT ALSO IT SEEMS TO BE HANDLING THE STRONG PAC JET COMING ONSHORE LATE INTO THE WEEKEND AND DRIVING ACROSS THE NORTHERN TIER STATES INTO EARLY NEXT WEEK...THUS CREATING THE FLATTER SOLUTION ACROSS THE CONUS AND THE DEEP TROUGH SEEN MORE PROGRESSIVE INTO THE ATLC BY TUESDAY. TRAVEL AROUND TURKEY DAY EVE STILL LOOKS GOOD...AND TEMPS LOOK TO BE MUCH WARMER AS WE APPROACH THANKSGIVING. SCHOTT && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 335 PM EST MON NOV 13 2006 .SYNOPSIS... 20Z WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS SHOWED A SHRTWV TROUGH STRETCHING FROM NW ONTARIO SOUTHWARD INTO ILLINOIS...LOCATED IN-BETWEEN STRONG RIDGING OVER THE EAST COAST INTO QUEBEC AND WEAK RIDGING BUILDING INTO WESTERN MINNESOTA. MORE ACTIVITY IS NOTED TO THE WEST OF THIS RIDGE...WITH A SHRTWV TROUGH COMING ACROSS THE U.S. ROCKIES AND ANOTHER SHRTWV LOCATED NEAR VANCOUVER ISLAND. FAIRLY STRONG UPPER JET PUNCHING INTO THE WEST TOO ON THE SOUTH SIDE OF THE SHRTWV WITH 175KT SEEN AT 200MB ON AIRCRAFT OBS AT 12Z. THE COMBINATION OF HEIGHT FALLS FROM THE SHRTWV TROUGH MOVING INTO UPPER MICHIGAN...A WARM CONVEYOR BELT OF MOISTURE AHEAD OF IT AND UPPER DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A 115KT JET STREAK MOVING NE THROUGH NORTHERN ONTARIO HELPED TO BRING SOME SNOW AND RAIN TO THE CWA. CURRENT RADAR LOOP AND OBSERVATIONS SHOW THAT ONLY THE EASTERN SECTIONS OF THE CWA ARE BEING AFFECTED BY PRECIPITATION NOW. OTHERWISE...LOW CLOUDS REMAIN ACROSS THE CWA AND ALL THE WAY WESTWARD INTO CENTRAL MINNESOTA (CEILINGS AROUND 1000 FT). THIS IS DUE TO MOISTURE TRAPPED UNDERNEATH A SUBSIDENCE INVERSION DEVELOPING BEHIND THE SHRTWV TROUGH. THE 16Z TAMDAR SOUNDING FROM BEMIDJI SHOWED THE INVERSION WELL WITH TEMPERATURES WARMING 6C AROUND 910MB. THE LOW CLOUDS HAVE BEEN ABLE TO MIX OUT ACROSS WESTERN MINNESOTA...HOWEVER HIGH CLOUDS CAN BE SEEN ALREADY SPREADING ACROSS MUCH OF THE PLAINS AHEAD OF THE NEXT SHRTWV TROUGH. AT THE SURFACE...A LOW PRESSURE TROUGH STRETCHED FROM NORTHERN ONTARIO INTO ILLINOIS...ASSOCIATED WITH THE SHRTWV MOVING ACROSS THE CWA. A HIGH PRESSURE RIDGE WAS LOCATED BEHIND THIS OVER MINNESOTA. FARTHER WEST...A 986MB LOW WAS LOCATED OVER SOUTHERN ALBERTA WITH A TIGHT PRESSURE GRADIENT EXTENDING EASTWARD INTO THE DAKOTAS. && .SHORT TERM (TONIGHT AND TUESDAY)... MAIN FORECAST CONCERN IS CLOUD COVER. TONIGHT...AS THE SHRTWV TROUGH CONTINUES PROGRESSING EASTWARD THIS EVENING...MORE SUBSIDENCE WILL OCCUR OVER THE CWA...HELPING TO END ANY LINGERING PRECIPITATION AND DRY OUT THE MID LEVELS. HOWEVER... THE SUBSIDENCE AGAIN SHOULD HELP TO LOCK IN THE LOW LEVEL MOISTURE...AND WITH VERY WEAK WIND FIELDS ASSOCIATED WITH THE HIGH PRESSURE RIDGE MOVING IN...DO NOT SEE THE CLOUDS GOING AWAY ANY TIME SOON. IN FACT...LATER TONIGHT AS THE UPPER RIDGE MOVES ACROSS UPPER MICHIGAN...HIGH CLOUDS OVER THE PLAINS SHOULD BEGIN TO MOVE IN. THE COMBINATION OF BOTH OF THESE SHOULD HELP TO KEEP TEMPERATURES UP TONIGHT. HAVE RAISED READINGS EVEN MORE...ESPECIALLY SINCE DEWPOINTS ARE FAIRLY HIGH. IN ADDITION...ADDED SOME PATCHY FOG INTO THE FORECAST AS VISIBILITIES THIS MORNING OVER MINNESOTA DROPPED INTO THE 3-4SM RANGE AFTER THE PRECIPITATION WENT THROUGH...AND SEE NO REASON WHY THIS SHOULD NOT HAPPEN AGAIN OVER THE CWA...ESPECIALLY WITH THE DRYING OCCURRING ALOFT. DID NOT MENTION ANY DRIZZLE SINCE THE WEAK WIND FIELDS DO NOT PROVIDE ANY SIGNIFICANT UPSLOPE. TUESDAY...SHRTWV OFF OF VANCOUVER ISLAND...IN ADDITION TO THE STRONG UPPER JET...BEGIN TO DIG DOWN INTO THE SOUTHERN PLAINS. IN RESPONSE TO THIS DIGGING...THE SHRTWV OVER THE ROCKIES IS PUSHED EAST AND THEN NORTHEAST INTO WISCONSIN AND LOWER MICHIGAN. LITTLE EFFECT WILL BE SEEN FROM THIS FEATURE...OTHER THAN FOR INCREASING HIGH CLOUDS GIVEN VERY DRY AIR THAT IS PROGGED IN THE 4000-10000 FT RANGE. HOWEVER...LOW CLOUDS WILL CONTINUE TO BE A PROBLEM...ESPECIALLY SINCE WINDS WILL TURN TO THE SE IN THE MORNING WITH THE PASSAGE OF THE HIGH PRESSURE RIDGE...CAUSING UPSLOPE FLOW OFF OF LAKE MICHIGAN FOR THE CENTRAL U.P. AND UPSLOPE FLOW OFF LAKE SUPERIOR FOR THE KEWEENAW. WITH MIXING INHIBITED BY THE HIGH CLOUDS SPREADING IN...THE LOW CLOUDS WILL LIKELY REMAIN LOCKED IN. WITH ALL THE CLOUD COVER...TEMPERATURES SHOULD NOT RISE A WHOLE LOT AND GOING TEMPS LOOKED REASONABLE. .LONG TERM (TUESDAY NIGHT THROUGH NEXT MONDAY)... CWA FCST TO BE UNDER THE DOMINATION OF A RDG AXIS TUE NGT. WITH LGT NE WIND OFF LK SUP AND PERSISTENT LO INVRN TO THE W OF WEAK SHRTWV PASSING TO THE E...SUSPECT LO CLDS WL BE PREVALENT UNDER AXIS OF LO PWAT ARND 0.25 INCH PER NGM/ETA MOS. WITH NEGLIGIBLE MSTR ADVECTION ON WED...SUSPECT LO CLD WL BE TENACIOUS WITH FCST NE LLVL FLOW AND SHOW ONLY MINOR DIURNAL IMPROVEMENT. VARIOUS MODEL MOS FCST TEMPS IN GOOD AGREEMENT AND RSNBL WITH LIMITED DIURNAL VARIATION IN TEMP. VIGOROUS CYC FCST TO DVLP OVER THE OH VALLEY ON WED FCST BY MAJORITY OF MODELS TO PASS FAR ENUF TO THE E LATE THIS WEEK SO THAT ACCOMPANYING PCPN PROGGED TO IMPACT ONLY THE ERN ZNS LATE THU INTO FRI. BONE DRY MID LVL ANTECEDENT AIRMASS WOULD SUG A SHARP WRN EDGE TO PCPN SHIELD. 12Z GFS FCST LO POSITION IS FARTHER W THAN MOST MODEL FCSTS...BUT KEEPS BEST UPR DVGC IN COUPLED UPR JET STRUCTURE E OF ERY. GIVEN THIS POSITION...ITS FCST DEEP SATURATION AT ERY AT 06Z FRI APPEARS OVERDONE. HAVE OPTED TO CUT POPS OVER THE WRN ZNS GIVEN LATEST FARTHER E MODEL FCST SCENARIOS AND GONE NO HIER THAN 50 POP OVER THE FAR E. PER NCEP DISCUSSION...HAVE TRENDED A BIT FASTER THAN 12Z GFS FOR TIMING OF IMPACTS. AIRMASS IN THE CYC NNW FLOW FARTHER W IS TOO WARM FOR LK EFFECT PCPN...AND GFS FCST SDNGS SHOW AN EXCESSIVELY DRY/STABLE ATMOSPHERE. SO NO POPS W OF P53-ESC THU THRU FRI. ON FRI NGT/SAT...BUMPED POPS UP TO HI CHC IN AREAS DOWNSTREAM OF LK SUP IN EXPECTED NW LLVL FLOW AS 12Z GFS/ECMWF SUPPORT 00Z ECMWF/ UKMET...00Z GFS ENSEMBLE MEAN...AND 06Z GFS/DGEX SHOWING SHRTWV PASSAGE THEN. EXTENDED GUIDANCE SHOWS UPR RDGING BLDG IN FOR LATE NEXT WEEKEND AFT TROF IN THE CNTRL LKS ON SAT BEGINS TO PULL OUT. WL MAINTAIN LO CHC POPS NR LK SUP FOR LINGERING LES ON SUN MRNG...BUT THEN GO DRY REST OF SUN AND MON WITH UPR RDGING BLDG IN. MON MRNG SHOULD BE A COLD ONE WITH HI PRES RDG AXIS/PWAT AS LO AS 0.1 INCH MOVING OVHD...SO WL GO BLO MOS GUIDANCE FOR INLAND AREAS. COORDINATED WITH APX. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AJ (SHORT-TERM) KC (LONG-TERM) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 206 PM EST MON NOV 13 2006 .UPDATE... KGRR-88D SHOWS PCPN AHEAD OF A TROUGH MOVING THROUGH THE REGION. PCPN IS NOW REACHING THE GROUND IN MIXED FORM WITH SOME WET SNOW LIGHT RAIN AND SLEET IN SPOTS. CLEARLY RUC SOUNDINGS ARE NOT DOING A GOOD JOB HANDLING THIS SITUATION. WILL UPDATE TO HIT MORE OF A MIX ACROSS THE EASTERN PORTION OF THE CWA THIS AFTERNOON AND EARLY EVENING. && .GRR WATCHES/WARNINGS/ADVISORIES...NONE. && $$ 93 mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 1206 PM CST MON NOV 13 2006 .UPDATE... RAIN CHANCES HAVE ENDED WITH PASSAGE OF BETTER MID LEVEL FORCING...ALTHOUGH CDFNT IS STILL MOVING THRU THE FA ATTM...IT WILL HAVE LITTLE IF ANYTHING TO WORK WITH AND NOT EXPECTING ANYTHING GREATER THAN A FEW SPKLS FOR THIS AFTERNOON. AREA OF LO CLOUDS WILL OVERSPREAD THE FA THIS AFTERNOON...BUT IN THE MEANTIME...LOOK FOR MIX OF SUN AND CLOUDS IN AREAS FROM THE STL METRO AREA SWD. DIURNAL ENHANCEMENT TO CLOUD IS OCCURRING ON ITS BACKSIDE AND WILL DELAY ANY CLEARING FOR THE WRN FA TIL LATE THIS AFTERNOON. TES && .DISCUSSION... N-S BAND OF RAIN OR SHOWERS MOVG EWD THRU THE CWA EARLY THIS MRNG AHD OF SHRTWV TROF ACRS THE NRN PLAINS AND ASSOCIATED WK CDFNT/SFC TROF EXTDG FM ERN MN S-SW THRU ERN OK. LATEST RUC ANLYS DEPICTS RELATIVELY STG 800-600 MB WAA EXTDG FM SERN IA S-SW THRU N CNTRL AR AHD OF LOW LVL TROF. BOTH NAM AND GFS MDLS ALSO SHOW UPR LVL DIVERGENCE ACRS MUCH OF THE CWA THIS MRNG AHD OF UPR LVL TROF. IT APRS THAT MOST OF THIS PCPN SHOULD PUSH E OF THE CWA BY THIS AFTN AS THE MID-UPR LVL TROF MOVES E OF THE AREA. THERE SHOULD BE AT LEAST PARTIAL CLRG OVR THE WRN PTN OF THE CWA THIS AFTN...BUT LOOKING AT MDL RH PROGS LOW LVL CLOUDINESS MAY LINGER OVR THE ERN PTN OF THE CWA THIS AFTN AND POSSIBLY INTO TGT. WK SHRTWVS MOVG FAIRLY RAPIDLY EWD THRU THE REGION MAY ALSO BRING SOME MID-UPR LVL CLOUDINESS TGT OVR THE CWA. MAX TEMPS SHOULD BE SLIGHTLY WRMR ON TUE WITH S-SWLY LOW LVL WNDS OVR THE CWA AHD OF DVLPG LOW PRESSURE SYSTEM IN THE LEE OF THE ROCKIES. CLOUD CVR WILL BE INCRSG BY TUE AFTN BUT PCPN SHOULD HOLD OFF TIL TUE NGT. RAIN/SHRA WILL SPREAD EWD THRU MOST OF THE CWA TUE NGT AHD OF DPNG MID-UPR LVL TROF MOVG EWD THRU THE PLAINS STATES. BOTH NAM AND GFS MDLS DVLP MID LVL CUTOFF LOW BY 12Z WED...ALTHOUGH THEY HAVE DIFFERING POSITIONS OF MID LVL LOW AND ASSOCIATED SFC LOW. GFS MDL IS FURTHER S WITH MID LVL LOW AND ASSOCIATED SFC LOW ON WED MOVG IT THRU NRN AR...WHILE THE NAM MDL HAS IT MOVG EWD THRU SRN MO. ALTHOUGH EITHER SOLUTION WOULD BRING PCPN TO MUCH OF THE CWA TUE NGT AND WED...THE GFS SOLUTION WOULD HAVE THE HIGHEST QPF A LTL FURTHER S AND HAVE SLIGHTLY COOLER TEMPERTURES FOR THE CWA. WILL GO WITH A COMPROMISE SOLUTION FOR NOW AS THERE IS STILL PLENTY OF UNCERTAINTY WITH THE TRACK OF THE MID LVL AND SFC LOW. WILL INCLUDE RELATIVELY HI POPS FOR TUE NGT AND WED ESPECIALLY OVR THE SRN HALF OF THE CWA. BOTH MDLS INDICATE INCRSG UPR LVL DIVERGENCE OVR THE CWA TUE NGT WITH APPROACH OF UPR LVL TROF AND IN LEFT EXIT REGION OF ULJ STREAK ACRS THE SRN PLAINS. LOOKING AT MID LVL Q CNVG...MID LVL MOISTURE AND 700 MB CVNG WILL LIKELY HAVE DEFORMATION TYPE PCPN ON WED INTO WED EVNG ACRS CNTRL AND SRN PTNS OF THE CWA JUST N OF THE TRACK OF THE DEEP MID LVL CLOSED LOW. GKS && .AVIATION... FOR THE 18Z TAFS...BAND OF POST-FRONTAL LO CLOUDS OVER THE NWRN HALF OF THE FA WILL MOVE INTO THE SERN HALF OF THE FA BEFORE LO LEVEL RIDGE OVERTAKES IT LATER THIS AFTERNOON AND THIS EVENING. THE NET RESULT IS EXPECTED TO BE THE STALLING OUT OF THESE LO CLOUDS OVER THE SERN HALF OF THE FA...WITH THE KSTL/KSUS TERMINALS ON THE NWRN EDGE FOR THIS EVENING...BEFORE THIS LO CLOUD BEGINS TO LOWER AND BUILD BACK TO THE NW LATE TONIGHT AS SELY LO LEVEL FLOW DEVELOPS OUT AHEAD OF THE NEXT STORM SYSTEM. THERE IS ALSO THE POTENTIAL FOR LIGHT MIST LATER TONIGHT...ESPECIALLY IN AREAS THAT CAN CLEAR OUT THIS EVENING...SUCH AS KCOU/KUIN. TES && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 244 PM EST MON NOV 13 2006 .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... SPRINKLES OVER IL/IN BORDER EARLIER TODAY WERE FALLING OUT OF A MID LEVEL DECK THAT IS PROGGED TO BE ALONG OR JUST PAST THE IN/OH BORDER BY THIS EVENING. MOST OF THE MOISTURE SHOULD HAVE ALREADY BEEN WRUNG OUT BY THIS TIME...WILL MONITOR BUT NOT EXPECT ANY PRECIP TO REACH THE GROUND WITH THE CENTER OF HIGH PRESSURE OVER CWA KEEPING A VERY DRY AIRMASS AROUND H8. BELOW THIS HOWEVER...AXIS OF RH MIN AT H9 IS SHOWING UP NICELY ON VIS IMAGE AND PROGGED TO MOVE W-E THROUGH CWA...KEEPING MUCH OF KY OUT OF THE LOW CLOUDS OVERNIGHT. MID LEVEL CLOUD COVER SHOULD BE ON THE DECREASE AS IT PASSES OVER THE OHVLY TONIGHT WITH THE WEAK SFC TROF UNDERNEATH IT GRADUALLY LIFTING N. LOW CLOUDS WILL WORK BACK IN TOMORROW FROM NW-SE EVEN AS SFC HI TRAVERSES OHVLY AHEAD OF NEXT SFC LOW COMING IN FROM THE MISWEST WED. E WINDS WILL PICK UP DURING THE DAY WED AHEAD OF SFC L MOVING UP OHRIVER. PRECIP WILL OVERSPREAD THE CWA FROM SW-NE OVER THE COURSE OF THE DAY...REACHING ERN CWA BY NIGHTFALL. GENERALLY RAISED OVERNIGHT TEMPS TONIGHT AND TOMORROW...WAS HESITANT TO CHANGE WED NIGHT WITH A STRONG W-E GRADIENT AS SFC L PASSES OVER CWA WITH EXPECTED PRECIP AND WRAP AROUND CAA TO THE WEST. LOWERED HIGH TEMPS IN THE NW BY A BIT TUES WITH THE THOUGHT OF SIGNIFICANT LOW CLOUDS HOLDING BACK ANY DIURNAL HEATING. DAYTIME HIGHS ON WED WERE CLOSE TO PREV FCST. KEPT THUNDER OUT OF FCST ATTM...UPPER LEVEL LOW IS SIGNIFICANTLY FURTHER SW FROM SFC CIRCULATION. DISJOINTED DYNAMICS MAY ALLOW FOR SOME CONVECTION TO GET STRONG ENOUGH FOR THUNDER...BUT MAJORITY OF THE RAIN WILL JUST BE SHOWERY ACTVITY. FRANKS && .LONG TERM /THURSDAY THROUGH MONDAY/... ON THURSDAY...AREA WILL BE UNDER THE INFLUENCE OF DEPARTING LOW PRESSURE. EXPECT SCATTERED RAIN SHOWERS DURING THE DAY WITH SNOW MIXING IN THURSDAY NIGHT IN COLDER AIR BEHIND THE LOW. FOR FRIDAY...HAVE FORECAST A CHANCE OF SHOWERS IN EASTERN COUNTIES WHERE LAKE MOISTURE MAY COME INTO PLAY. AFTER A BRIEF DRY PERIOD ON SATURDAY...AN UPPER TROUGH WILL BRING A CHANCE OF SHOWERS SATURDAY NIGHT AND SUNDAY TO EASTERN LOCATIONS AGAIN. HIGH PRESSURE BUILDING IN FROM THE WEST WILL DRY THINGS OUT FOR NEXT MONDAY. PERSISTENT UPPER TROUGH OVER EASTERN CONUS POINTS TO TEMPERATURES AT OR BELOW AVERAGE THROUGH THE PERIOD. WENT A BIT BELOW MEX GUIDANCE THURSDAY THROUGH SATURDAY...THEN A BIT ABOVE GUIDANCE FOR SUNDAY AND MONDAY. && .AVIATION /18Z-18Z/... WEDGE OF CLR SKIES CONTINUES TO MOVE E THRU THE WESTERN TAFS ATTM. HAVE IT TIMED TO ILN WITHIN THE NEXT HOUR AND TO CMH/LCK BY 21Z. NEXT PROBLEM IS HOW QUICKLY THE CLOUDS OVER IN WILL WORK BACK INTO THE TAFS AND AT WHAT LEVEL. MODELS DONT SEEM TO BE HANDLING THINGS VERY WELL. THE NAM AND RUC HAVE THE CLRG...BUT FORM CU IN IT WITHIN THE NEXT FEW HOURS. THEY DONT BRING THE HIGHER H9 MOISTURE BACK IN TIL AFT 03Z. DECIDED TO EXTRAPOLATE THE CURRENT SATELLITE AND OBS AND BRING THEM IN...WHICH WOULD BRING THE CLOUDS BACK INTO CVG/LUK AROUND 22Z WITH CIGS AROUND 1K FT. IFR CIGS SHOULD REACH DAY/ILN AROUND 00Z AND CMH/LCK AROUND 02Z. THIS IFR DECK ONLY SEEMS 50 TO 75 MILES WIDE AS CIGS OVER CENTRL IL ARE AROUND 5K. RAISED CIGS FOR A FEW HOURS TO VFR...BEFORE ALLOWING HIGHER H9 MOISTURE TO WORK BACK INTO THE TAFS AROUND 12Z. SITES && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1257 PM EST MON NOV 13 2006 .AVIATION /18Z-18Z/... WEDGE OF CLR SKIES CONTINUES TO MOVE E THRU THE WESTERN TAFS ATTM. HAVE IT TIMED TO ILN WITHIN THE NEXT HOUR AND TO CMH/LCK BY 21Z. NEXT PROBLEM IS HOW QUICKLY THE CLOUDS OVER IN WILL WORK BACK INTO THE TAFS AND AT WHAT LEVEL. MODELS DONT SEEM TO BE HANDLING THINGS VERY WELL. THE NAM AND RUC HAVE THE CLRG...BUT FORM CU IN IT WITHIN THE NEXT FEW HOURS. THEY DONT BRING THE HIGHER H9 MOISTURE BACK IN TIL AFT 03Z. DECIDED TO EXTRAPOLATE THE CURRENT SATELLITE AND OBS AND BRING THEM IN...WHICH WOULD BRING THE CLOUDS BACK INTO CVG/LUK AROUND 22Z WITH CIGS AROUND 1K FT. IFR CIGS SHOULD REACH DAY/ILN AROUND 00Z AND CMH/LCK AROUND 02Z. THIS IFR DECK ONLY SEEMS 50 TO 75 MILES WIDE AS CIGS OVER CENTRL IL ARE AROUND 5K. RAISED CIGS FOR A FEW HOURS TO VFR...BEFORE ALLOWING HIGHER H9 MOISTURE TO WORK BACK INTO THE TAFS AROUND 12Z. SITES && .PREV DISCUSSION... /ISSUED 1145 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY/... WEDGE OF CLRG FORMED IN ERN IN AND SHOULD WORK NE DURING THE AFTN. ADJUSTED CLOUD COVER TO GO MORE OPTIMISTIC THIS AFTN. SITES PREV DISCUSSION... /ISSUED 1037 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH TONIGHT/... LOW LEVEL MOISTURE REMAINS TRAPPED UNDER STRONG INVERSION. BACK EDGE OF ST IS ON THE IL/IN BORDER ATTM. EVEN IF INVERSION DOES BREAK THERE IS A LOT OF MID CLOUDS STREAMING OVER. ADDITIONAL MOISTURE ASSOCIATED WITH CDFNT IN IL IS WORKING E QUICKLY. INCREASED CLOUD COVER TODAY AND TONIGHT. IN ADDITION...LOWERED TEMPS FOR TODAY A LITTLE...ESPECIALLY IN THE NW WHERE TEMPERATURES WERE RUNNING WELL BELOW THE CURVE. SITES PREV DISCUSSION... /ISSUED 639 AM EST MON NOV 13 2006/ AVIATION /12Z-12Z/... 06Z NAM/GFS SOLNS HAVE PICKED UP ON CURRENT LOCATION OF SC DECK A LITTLE BIT BETTER THAN PREV RUNS. HOWEVER...OVERALL CONFIDENCE IN CLOUD FCST REMAINS LOW. BEGINNING TO THINK THAT MVFR CIGS WILL HOLD FOR MUCH OF THE DAY YET AGAIN TODAY AS LO LVL FLO REMAINS FAIRLY LIGHT ALL DAY AHEAD OF APPCHG WEAK FRNTL BNDRY. EASTERLY FLO IN BNDRY LYR BEGINNING TO SLACK AND VEER TO SRLY...BUT BACK EDGE OF SC DECK HAS NOW BEEN PUSHED WEST ALL THE WAY INTO CNTRL INDIANA/KENTUCKY. MODEL SOUNDINGS KEEPING INVERSION STRONGER THAN PREV THOUGHT WITH NOT AS MUCH BNDRY LYR MIXING. KCVG/KLUK PROBABLY HAVE THE BEST SHOT TO BREAK OUT OF MVFR CIGS BY MID/LATE AFTN...BEING REPLACED BY EXTENSIVE AC DECK AHEAD OF FRNTL BNDRY. AT THE OTHER TAF SITES...WILL MAINTAIN MVFR CIGS INTO THE EVNG HOURS. BNDRY APPEARS TO WASH OUT ACRS FCST AREA THIS EVNG...BUT INCREASING AMOUNTS OF LO LVL MOISTURE WILL SERVE TO EITHER REESTABLISH OR REINFORCE SC DECK INTO MVFR LEVELS LATE TONIGHT. RYAN PREV DISCUSSION... /ISSUED 301 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH WEDNESDAY/... SURFACE ANALYSIS SHOWS HIGH PRESSURE RIDGE FROM GREAT LAKES INTO THE TENNESSEE VALLEY. SATELLITE IMAGERY SHOWS STRATUS HOLDING TIGHT OVER FORECAST AREA CIRRUS MOVING IN FROM THE WEST. GFS AND NAM ARE IN PRETTY GOOD AGREEMENT THROUGH THE FORECAST PERIOD. WEAK SURFACE HIGH WILL DOMINATE WEATHER THROUGH TUESDAY NIGHT. A DIGGING UPPER TROF WILL QUICKLY DEEPEN A SURFACE LOW AND MOVE IT INTO THE OHIO VALLEY ON WEDNESDAY. THIS WILL BRING PLENTY OF SHOWERS BEGINNING WEDNESDAY AND LASTING INTO THRU FRIDAY NIGHT. GFS 1000-850 THICKNESSES SUGGEST A MIX OF SNOW OR ALL SNOW BY FRIDAY NIGHT. AS FOR TODAYS CLOUD FORECAST IT IS NOT STRAIGHT FORWARD. STRATUS IS STILL HANGING TIGHT WITH HIGH LEVEL CLOUDS WORKING IN FROM THE WEST. NAM/RUC SHOWING RH DECREASING TO SOME DEGREE TODAY. THINK THERE WILL BE SOME MIXING OUT...BUT HIGH LEVEL CLOUDS WILL DETER THAT TO SOME DEGREE ESPECIALLY THIS TIME OF YEAR. THUS WILL GO WITH BECOMING PARTLY CLOUDY/SUNNY FOR THIS AFTERNOON...HOWEVER CONFIDENCE IS NOT REAL HIGH. WILL REMOVE THE MENTION OF THUNDER FOR WEDNESDAY. BOTH THE NAM AND GFS SHOW NO ELEVATED OR SURFACE BASED INSTABILITY. MAV TEMPS LOOK REASONABLE. THE ONLY CHANGES WERE MADE IN THE FIRST AND FIFTH PERIODS WERE MAV WAS LOWERED SEVERAL DEGREES. TIPTON PREV DISCUSSION... /ISSUED 315 PM EST SUN NOV 12 2006/ LONG TERM /WEDNESDAY THROUGH SUNDAY/... LOOKS LIKE MODELS CONTINUE TO SLOW UP SYSTEM FOR MID WEEK WITH ONSET OF PRECIPITATION MAINLY AFTER 06Z WED BUT BETTER CHANCES AFTER 12Z WED. LOW PRESSURE SYSTEM CENTERED OVER WESTERN IL AT AROUND 12Z WED WILL MOVE SLOWLY ESE AS A SECOND LOW DEVELOPS OVER WESTERN SC. THEN THE IL/IN LOW WILL MOV NE ACROSS OH INTO THE GRT LKS BY 18Z THU. THIS COINCIDES WITH THE MOVEMENT OF AN UPPER LEVEL LOW. THE UPPER LEVEL LOW AND SURFACE LOW WILL MOVE WELL NORTH OF THE GRT LKS INTO CANADA FRI THROUGH SUN. THIS WILL KEEP THE REGION IN A NW FLOW WITH THE MINIMAL THREAT FOR RAIN/SNOW SHOWERS THROUGH SUNDAY. BEST CHANCES OF PRECIPITATION WILL BE WED INTO THU NIGHT. A MIX OF RAIN SHOWERS AND SNOW SHOWERS MAY BE SEEN...MAINLY EARLY THU MORNING AND FRIDAY NIGHT. AT THIS TIME...HAVE RESTRICTED MENTION OF SLIGHT CHANCE RAIN/SNOW SHOWERS TO SATURDAY NIGHT IN LATER PERIODS OF EXTENDED. HIGHS START OUT IN THE 50S WED AND LOWS THU IN THE 40S WITH A GENERAL COOLING TREND THROUGH THE REMAINDER OF THE EXTENDED PERIOD. EXPECT HIGHS FOR THE MOST PART IN THE 40S AND LOWS IN THE 30S. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1145 AM EST MON NOV 13 2006 .SHORT TERM /REST OF TODAY/... WEDGE OF CLRG FORMED IN ERN IN AND SHOULD WORK NE DURING THE AFTN. ADJUSTED CLOUD COVER TO GO MORE OPTIMISTIC THIS AFTN. SITES && .PREV DISCUSSION... /ISSUED 1037 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH TONIGHT/... LOW LEVEL MOISTURE REMAINS TRAPPED UNDER STRONG INVERSION. BACK EDGE OF ST IS ON THE IL/IN BORDER ATTM. EVEN IF INVERSION DOES BREAK THERE IS A LOT OF MID CLOUDS STREAMING OVER. ADDITIONAL MOISTURE ASSOCIATED WITH CDFNT IN IL IS WORKING E QUICKLY. INCREASED CLOUD COVER TODAY AND TONIGHT. IN ADDITION...LOWERED TEMPS FOR TODAY A LITTLE...ESPECIALLY IN THE NW WHERE TEMPERATURES WERE RUNNING WELL BELOW THE CURVE. SITES PREV DISCUSSION... /ISSUED 639 AM EST MON NOV 13 2006/ AVIATION /12Z-12Z/... 06Z NAM/GFS SOLNS HAVE PICKED UP ON CURRENT LOCATION OF SC DECK A LITTLE BIT BETTER THAN PREV RUNS. HOWEVER...OVERALL CONFIDENCE IN CLOUD FCST REMAINS LOW. BEGINNING TO THINK THAT MVFR CIGS WILL HOLD FOR MUCH OF THE DAY YET AGAIN TODAY AS LO LVL FLO REMAINS FAIRLY LIGHT ALL DAY AHEAD OF APPCHG WEAK FRNTL BNDRY. EASTERLY FLO IN BNDRY LYR BEGINNING TO SLACK AND VEER TO SRLY...BUT BACK EDGE OF SC DECK HAS NOW BEEN PUSHED WEST ALL THE WAY INTO CNTRL INDIANA/KENTUCKY. MODEL SOUNDINGS KEEPING INVERSION STRONGER THAN PREV THOUGHT WITH NOT AS MUCH BNDRY LYR MIXING. KCVG/KLUK PROBABLY HAVE THE BEST SHOT TO BREAK OUT OF MVFR CIGS BY MID/LATE AFTN...BEING REPLACED BY EXTENSIVE AC DECK AHEAD OF FRNTL BNDRY. AT THE OTHER TAF SITES...WILL MAINTAIN MVFR CIGS INTO THE EVNG HOURS. BNDRY APPEARS TO WASH OUT ACRS FCST AREA THIS EVNG...BUT INCREASING AMOUNTS OF LO LVL MOISTURE WILL SERVE TO EITHER REESTABLISH OR REINFORCE SC DECK INTO MVFR LEVELS LATE TONIGHT. RYAN PREV DISCUSSION... /ISSUED 301 AM EST MON NOV 13 2006/ SHORT TERM /REST OF TODAY THROUGH WEDNESDAY/... SURFACE ANALYSIS SHOWS HIGH PRESSURE RIDGE FROM GREAT LAKES INTO THE TENNESSEE VALLEY. SATELLITE IMAGERY SHOWS STRATUS HOLDING TIGHT OVER FORECAST AREA CIRRUS MOVING IN FROM THE WEST. GFS AND NAM ARE IN PRETTY GOOD AGREEMENT THROUGH THE FORECAST PERIOD. WEAK SURFACE HIGH WILL DOMINATE WEATHER THROUGH TUESDAY NIGHT. A DIGGING UPPER TROF WILL QUICKLY DEEPEN A SURFACE LOW AND MOVE IT INTO THE OHIO VALLEY ON WEDNESDAY. THIS WILL BRING PLENTY OF SHOWERS BEGINNING WEDNESDAY AND LASTING INTO THRU FRIDAY NIGHT. GFS 1000-850 THICKNESSES SUGGEST A MIX OF SNOW OR ALL SNOW BY FRIDAY NIGHT. AS FOR TODAYS CLOUD FORECAST IT IS NOT STRAIGHT FORWARD. STRATUS IS STILL HANGING TIGHT WITH HIGH LEVEL CLOUDS WORKING IN FROM THE WEST. NAM/RUC SHOWING RH DECREASING TO SOME DEGREE TODAY. THINK THERE WILL BE SOME MIXING OUT...BUT HIGH LEVEL CLOUDS WILL DETER THAT TO SOME DEGREE ESPECIALLY THIS TIME OF YEAR. THUS WILL GO WITH BECOMING PARTLY CLOUDY/SUNNY FOR THIS AFTERNOON...HOWEVER CONFIDENCE IS NOT REAL HIGH. WILL REMOVE THE MENTION OF THUNDER FOR WEDNESDAY. BOTH THE NAM AND GFS SHOW NO ELEVATED OR SURFACE BASED INSTABILITY. MAV TEMPS LOOK REASONABLE. THE ONLY CHANGES WERE MADE IN THE FIRST AND FIFTH PERIODS WERE MAV WAS LOWERED SEVERAL DEGREES. TIPTON PREV DISCUSSION... /ISSUED 315 PM EST SUN NOV 12 2006/ LONG TERM /WEDNESDAY THROUGH SUNDAY/... LOOKS LIKE MODELS CONTINUE TO SLOW UP SYSTEM FOR MID WEEK WITH ONSET OF PRECIPITATION MAINLY AFTER 06Z WED BUT BETTER CHANCES AFTER 12Z WED. LOW PRESSURE SYSTEM CENTERED OVER WESTERN IL AT AROUND 12Z WED WILL MOVE SLOWLY ESE AS A SECOND LOW DEVELOPS OVER WESTERN SC. THEN THE IL/IN LOW WILL MOV NE ACROSS OH INTO THE GRT LKS BY 18Z THU. THIS COINCIDES WITH THE MOVEMENT OF AN UPPER LEVEL LOW. THE UPPER LEVEL LOW AND SURFACE LOW WILL MOVE WELL NORTH OF THE GRT LKS INTO CANADA FRI THROUGH SUN. THIS WILL KEEP THE REGION IN A NW FLOW WITH THE MINIMAL THREAT FOR RAIN/SNOW SHOWERS THROUGH SUNDAY. BEST CHANCES OF PRECIPITATION WILL BE WED INTO THU NIGHT. A MIX OF RAIN SHOWERS AND SNOW SHOWERS MAY BE SEEN...MAINLY EARLY THU MORNING AND FRIDAY NIGHT. AT THIS TIME...HAVE RESTRICTED MENTION OF SLIGHT CHANCE RAIN/SNOW SHOWERS TO SATURDAY NIGHT IN LATER PERIODS OF EXTENDED. HIGHS START OUT IN THE 50S WED AND LOWS THU IN THE 40S WITH A GENERAL COOLING TREND THROUGH THE REMAINDER OF THE EXTENDED PERIOD. EXPECT HIGHS FOR THE MOST PART IN THE 40S AND LOWS IN THE 30S. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SHORT TERM... oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 300 PM CST MON NOV 13 2006 .SHORT TERM...THROUGH THURSDAY NIGHT PRIMARY FORECAST CONCERNS WERE FOCUSED ON CLOUD TRENDS AND FOG POTENTIAL TONIGHT...THEN PRECIPITATION CHANCE/TYPE TUESDAY THROUGH WEDNESDAY NIGHT. AFTERNOON SURFACE ANALYSIS INDICATED COLD FRONT HAD PUSHED INTO EASTERN WI AND NORTHERN IL. IN THE WAKE OF THE FRONT...VISIBLE SATELLITE IMAGERY SHOWED LOW CLOUDS WERE CLEARING EASTWARD SLOWLY... IN SPITE OF STRONG SUBSIDENCE BEHIND DEPARTING UPPER LEVEL WAVE. FURTHER WEST...HIGH CLOUDS ADVANCING ACROSS THE PLAINS IN RETURN SOUTHERLY FLOW AND WARM AIR ADVECTION. WATER VAPOR IMAGERY INDICATED SEVERAL SHORT WAVES EMBEDDED IN STRONG UPPER LEVEL FLOW COMING IN FROM THE EASTERN PACIFIC. 12Z 13NOV06 MODEL SOLUTIONS CONTINUED TO HAVE EXCELLENT CLUSTERING WITH RESPECT TO UPPER LEVEL SURFACE FEATURES AFFECTING THE FORECAST AREA THROUGH MIDWEEK. MODEL CONSENSUS PRODUCES HIGH CONFIDENCE FOR CLOSED 500MB LOW DEVELOPING OVER THE MID MISSISSIPPI AND LOWER OHIO VALLEY BY WEDNESDAY. SYSTEM THEN SHIFTS INTO THE GREAT LAKES AND SOUTHEAST CANADA BY THURSDAY. THIS SHOULD KEEP HEAVIEST...IF NOT MOST OF THE QPF ASSOCIATED WITH THIS SYSTEM...SOUTH AND EAST OF OUR FORECAST AREA. NCEP SREF ENSEMBLE SUPPORTED THIS SOLUTION. TONIGHT...BASED ON CLEARING OCCURRING PER VISIBLE SATELLITE IMAGERY...LATEST RUC AND NAM/WRF APPEAR ON TARGET WITH LOW CLOUDS CONTINUING TO CLEAR EASTWARD THIS EVENING AND OVERNIGHT. BOUNDARY LAYER WILL BE MOIST AND WITH LIGHT WINDS...ATMOSPHERE SHOULD BE PRIMED FOR SOME FOG. THE CAVEAT TO THIS IS GOING TO BE ONSET OF HIGH CLOUDS. TIME/HEIGHT CROSS SECTIONS SUGGEST HIGH CLOUDS WILL CONTINUE SPREADING EASTWARD...WHICH SHOULD HINDER RADIATIONAL COOLING AND THUS POTENTIAL FOR WIDESPREAD DENSE FOG DEVELOPMENT. PATCHY FOG INTRODUCED BY LAST NIGHTS MIDNIGHT SHIFT FOR PARTS OF SOUTHWEST AND CENTRAL WI APPEARS VERY REASONABLE...ESPECIALLY SINCE MUCH OF THIS AREA WILL HAVE POTENTIAL FOR LONGEST PERIOD OF RADIATIONAL COOLING BEFORE ONSET OF HIGH CLOUDS. TUESDAY INTO WEDNESDAY NIGHT...FORECAST AREA SHOULD BE BETWEEN UPPER LEVEL WAVE ADVANCING ACROSS SOUTHERN CANADA AND MORE VIGOROUS UPPER LEVEL AND SURFACE WAVE MOVING THROUGH MID MISSISSIPPI VALLEY. BEST DYNAMICS ASSOCIATED WITH DEEP LAYERED Q-G CONVERGENCE RESIDES SOUTH OF THE FORECAST AREA WHERE 500MB LOW CLOSES OFF. BELIEVE BEST PROBABILITIES OF QPF WILL BE CONFINED TO SOUTHERN MOST PART OF THE FORECAST AREA. THEREFORE...PRECIPITATION PROBABILITIES WERE REMOVED OR REDUCED...ESPECIALLY OVER PARTS OF CENTRAL AND NORTH CENTRAL WI. NCEP SREF AND BUFKIT PRECIPITATION TYPE ALGORITHMS SUGGEST HIGHER PROBABILITIES OF RAIN THAN SNOW ASSOCIATED WITH THIS SYSTEM. CURRENT DATA BASE SUPPORTS RAIN OR SNOW AT THIS TIME. PREFERRED TO ALLOW FURTHER EVALUATION OF SUBSEQUENT MODEL DATA BEFORE ATTEMPTING TO PROVIDE MORE DETAIL WITH RESPECT TO PRECIPITATION TYPE. .LONG TERM...FRIDAY THROUGH MONDAY FRIDAY INTO SATURDAY...ECMWF AND GFS HAVE COME INTO MUCH BETTER AGREEMENT ON POSITION OF SURFACE AND UPPER LEVEL FEATURES. IN FACT... BOTH MODELS HAVE BEEN DEVELOPING CONSENSUS ON A SHORT WAVE DROPPING SOUTHEASTWARD ACROSS THE UPPER MISSISSIPPI VALLEY IN THIS TIME FRAME. GFS SUGGESTS CLOUDS AND SOME LIGHT QPF POTENTIAL. GROWING MODEL CONSENSUS CERTAINLY INCREASES FORECAST CONFIDENCE THAT MORE CLOUD COVER SHOULD BE ADDED TO CURRENT DATA BASE. FOR NOW...OPTED NOT TO ADD ANY LIGHT QPF AWAITING FURTHER EVALUATION OF SUBSEQUENT MODELS. SUNDAY INTO MONDAY...ECMWF AND GFS WERE IN GOOD AGREEMENT WITH RESPECT TO RIDGING AT THE SURFACE AND ALOFT. THEREFORE...FORECAST CONFIDENCE REMAINS FAIRLY HIGH FOR A PERIOD OF DRY WEATHER. NO CHANGES WERE MADE TO THIS PORTION OF THE EXTENDED OUTLOOK. && .ARX WATCHES/WARNINGS/ADVISORIES... MN...NONE. IA...NONE. WI...NONE. && $$ THOMPSON wi