AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 815 PM EST THU NOV 18 2004 NEG TILTED S/WAVE TROUGH APPROACHING THE MID/LOWER MS VALLEY, W/ A TRAILING POS TILTED S/WAVE TROUGH OVER THE DESERT SW. DOWNSTREAM UPPER RIDGE HAS SHIFTED EWD, EXTENDING FROM THE OH VALLEY TO FL. SURFACE RIDGE REMAINS ORIENTED ALONG THE APPALACHIANS. UPPER LEVEL DISTURBANCE AHEAD OF TROUGH IS PROVIDING SUFFICIENT LIFT TO PRODUCE AREAS OF -RA FROM SRN AL TO NRN GA THIS EVENING. LOW-LEVELS REMAIN DRY ENOUGH THAT MOST OF THE PCPN IS EVAPORATING BEFORE REACHING THE GROUND. HOWEVER, WILL ADD A 20 POP FOR -RA OVER WRN ZONES. OTHERWISE, AMPLE MID/UPPER CLOUDS REQUIRE A REVISION OF SKY TO M/CLOUDY. CONSEQUENTLY, MIN TEMPS WILL BE RAISED A CATEGORY IN SOME AREAS AS WELL. ELY WINDS AROUND 10 KTS W/ 2-3 FT SEAS PREVAIL OVER THE MARINE AREA THIS EVENING. THE MOB BUOY HAS BEEN REPORTING SE WINDS NEAR 15 KNOTS THE PAST SEVERAL HOURS WHERE PRESSURE GRADIENT IS A BIT TIGHTER. BOTH RUC/ETA VEER WINDS FROM E TO SE OVERNIGHT. WINDS/SEAS INCREASE TO 10-15 KTS/2-4 FT OVER WRN MARINE LEGS, AND REMAIN 10 KTS/2-3 FT OVER ERN LEGS, RESPECTIVELY. WILL ADDRESS THESE TRENDS IN THE CWF UPDATE. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ MAJ fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 1102 AM EST THU NOV 18 2004 UPDATED FIRE WEATHER AND WWA SECTION FOR RED FLAG WARNING. .DISCUSSION...THE UPPER LOW IS MOVING ENE ACROSS OK THIS MORNING. THE DOWNSTREAM RIDGE AXIS IS NOW OVERHEAD LOCALLY AND EXTENDS NWD INTO LOWER MI. CIRRUS CLOUDS ARE SPILLING OVER THE RIDGE INTO THE CWFA. SURFACE HIGH PRESSURE REMAINS CENTERED OVER THE SE CONUS. THE 12Z KTLH SOUNDING SHOWS THAT VERY DRY AIR REMAINS IN PLACE OVER THE AREA WITH THE PW JUST 0.41 INCHES. SEE FIRE WEATHER DISCUSSION BELOW. NO PUBLIC FORECAST UPDATE IS PLANNED TODAY. && .MARINE...WINDS OVER THE COASTAL WATERS ARE E AT 10-15 KT THIS MORNING. SEAS AT THE BUOYS HAVE BEEN RUNNING 3-4 FT. THIS IS ALL REFLECTED IN THE CURRENT FORECAST, SO NO CHANGES WILL BE NECESSARY. WINDS & SEAS ARE FORECAST TO REMAIN BELOW CAUTION THROUGH MON. WINDS WILL VEER TO A MORE SLY COMPONENT BY FRI NIGHT AND THIS SHOULD THEN PERSIST THROUGH THE REMAINDER OF THE PERIOD. && .FIRE WEATHER...YESTERDAY'S MIXED LAYER REMAINS EVIDENT ABOVE THE SURFACE INVERSION IN THIS MORNING'S KTLH SOUNDING. WE ARE CONCERNED THAT THE DEW POINT WILL ONCE AGAIN MIX OUT LOWER THAN INDICATED BY MOS, AS HAPPENED YESTERDAY. THE LATEST RUC40 SHOWS RED FLAG CRITERIA DEVELOPING. A MITIGATING FACTOR IS THAT THE LOW LEVEL FLOW HAS MORE OF AN ELY COMPONENT THAN YESTERDAY, AND MOISTURE LEVELS HAVE INCREASED SUBSTANTIALLY BELOW 800 MB. WE SHOULD NOT SEE ANOTHER 7 HOUR EVENT, BUT 5 TO 6 HOUR DURATIONS WILL BE POSSIBLE ACROSS OUR INLAND FL ZONES. THEREFORE, A RED FLAG WARNING HAS BEEN ISSUED. && .PREV DISCUSSION... 200 AM EST THU NOV 18 2004 SHORT TERM...TODAY THROUGH FRIDAY NIGHT. HIT RED FLAG WARNING CONDITIONS YESTERDAY...AS QUITE A BIT OF DRY AIR MIXED OUT. TODAY LOOKING TO BE A MARGINAL EVENT OVER INLAND LOCALES OF N FL...SO WILL GO WITH STATEMENT OF 1-3 HOURS POSSIBLE INLAND THIS AFTERNOON. OTHERWISE...TODAY HIGH PRESSURE AT THE SURFACE WITH ONLY CIRRUS EXPECTED. WINDS A BIT MORE EAST AS SURFACE HIGH DRIFTS A BIT MORE EAST. WARMER TEMPS TO THE REACH THE LOWER & SOME MID 70S. TONIGHT...PARTLY CLOUDY & MILDER WITH LIGHT SE FLOW BY MORNING. LOW CHANCE OF SHOWERS FL PANHANDLE FRIDAY MORNING TO AFTERNOON...MOST OTHERS SLIGHT TO NIL. FRIDAY NIGHT THE CHANCES OF RAIN REMAIN LOW TO SLIGHT...AS THE SURFACE HIGH CONTINUES TO WEAKEN & THE UPPER SYSTEM IN THE PLAINS MAKES SOME PROGRESS EAST. LONG TERM...SATURDAY THROUGH WEDNESDAY. MODELS SIMILAR WITH SLOWING DOWN APPROACHING SYSTEM AS THE SURFACE HIGH HOLDS OFF THE EAST COAST...AS WELL AS THE THE UPPER RIDGE. POP FORECASTS WILL REMAIN IN CHANCE CAT MUCH OF PERIOD UNTIL THE SYSTEM MAKES MORE PROGRESS EAST. A BOUNDARY SETTLES NEAR CWA ON MONDAY...BUT THEN LIFTS BACK NORTH ON TUESDAY THROUGH WEDNESDAY. THEN A COLD FRONT IS SEEN IN THE GFS FOR THURSDAY. SURFACE HIGH BUILDS IN FOR FRIDAY. TEMPS WILL GENERALLY BE A BIT COOLER THAN NORMAL FOR HIGHS...WHILE LOWS A BIT WARMER. && .PRELIMINARY POINT TEMPS/POPS... TLH 74 48 75 57/ 00 10 20 20 PFN 74 56 75 62/ 00 20 30 30 DHN 72 54 72 58/ 00 20 30 30 ABY 73 49 74 56/ 00 10 20 20 VLD 74 49 76 56/ 00 10 10 10 CTY 75 49 77 58/ 00 10 10 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...RED FLAG WARNING 11 AM UNTIL SUNSET FOR FLZ11-13-16>19-26-27. && $$ CURRENT...WOOL/18 PREVIOUS...MCT fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 651 AM EST THU NOV 18 2004 .AVIATION... EXACERBATING SITU THIS AM WRT TO TAFS. MODEL GUIDANCE AS A WHOLE MUCH TOO PESSIMISTIC GIVEN UPSTREAM TRENDS ACRS IL INTO WRN IN. INCOMING MID/HIGH CLD SHIELD RAPIDLY OVERSPREADING THE AREA HELPING MATTERS AS IS RENEWED BUT SCT SHRA. OF IMMEDIATE CONCERN IS AREA OF LIFR WHICH HAD DEVELOPED UPSTREAM IN WI ALG WK SFC TROUGH. MORE OF AN ISSUE FOR SBN AS BNDRY PIVOTS SWD IN RESPONSE TO BACKING LL FLW AHD OF STG SRN STREAM LOW HEADED FOR THE AREA TONIGHT. FWA SHLD STAY S BUT POSES MORE OF A CHALLENGE GIVEN LG STRATUS WEDGE OVR OH LIKELY NOT BREAKING UP THIS AFTN AND POTENTIAL TO ADVT WWD INTO FWA AREA LTR TDA. DAY SHIFT WILL NEED TO MONITOR THAT OTHERWISE FOLLOWING MORE OPTIMISTIC RH TRENDS SEEN IN SHRT TERM RUCII DATA AND OBSERVATIONS. && .SHORT TERM... IMPRESSIVE SRN STREAM SYS POISED TO OPEN AND EJECT NE AHD OF POWERHOUSE NRN STREAM WV COMING INTO BC THIS AM. FLOOD GATE OF MSTR IN PLACE DOWNSTREAM W/00Z H2O PLOT TELLING THE TALE AS MANY RAOBS AOA 200% OF NORMAL. MSTR PLUME NOT GOING ANYWHERE TOO SOON AND GIVEN CONTD PROXIMITY OF LL THETA GRADIENT AND WK UPR WV ALG SRN EDGE OF WESTERLIES UPSTREAM OVR WI...HAVE ADDED MORE POPS THIS AFTN S OF IN/MI BORDER. ALREADY COMPOSITE RADARS SHOWING QUITE A FEW SHOWERS OVR CNTRL/SRN WI AND INTO NRN IL AND MAY HAVE TO BACK THINGS UP FURTHER IN GRIDS BEFORE ALL IS SAID AND DONE ON THIS FTR FOR TDA. OTHERWISE OTHER PROBLEM THAT BEARS WATCHING IS FOG WHICH HAS BECOME DENSE ACRS NE IN CONJUCTION W/LOSS OF MID LVL CLD DECK...ALTHOUGH THAT APPEARS TO BE SHRT LIVED GIVEN ADDNL MID CLDS STREAMING EWD AHD OF WK WV IN WI AND MIGHT SQUEEK BYE WITHOUT HAVING TO POST AN ADVISORY. LTL CHC FOR INSOLATIVE INPUT THIS AFTN AND VRY LIMITED MIXING AGAIN SUGGEST CUTTING TEMPS BACK SOME FOR THIS AFTN ALTHOUGH PASSAGE OF WI UPR TROUGH AND BACKING LL WINDS IN RESPONSE TO EJECTING SRN WV LOOK TO PULL DOWN A BIT DRIER AIR LOCATED UP N BUT SRN EXTENT BEFORE STALLING TONIGHT HIGHLY QUESTIONABLE. HAVE MY DOUBTS IT WILL MAKE IT MUCH BEYOND THE BORDER AND HAVE REFINED OVERNIGHT MINS TO CORRELATE. PRESENCE OF LL THETA GRADIENT AND INCREASING UPR SPRT IN TANDEM W/DEEP MSTR PLUME IN PLACE SPELL CAT TO LIKELY POPS THEN TOO EXCEPT FAR NE BY DAYBREAK FRI. && .LONG TERM... FRIDAY THROUGH WEDNESDAY. MODELS STILL FOCUSING MUCH OF THE PRECIP ACROSS THE FORECAST AREA MAINLY FRI AM...WITH THE BULK OF THE LIFT SHIFTING NORTHEAST DURING THE AFTERNOON. HAVE OPTED TO GO CAT POPS ALL DAY...BUT LOW END OF CAT POPS IN SW COUNTIES IN AFTERNOON TO SHOW SOMEWHAT OF A DECREASING TREND. WITH EXPECTED CLOUD CVR AND PRECIP...NOT EXPECTING MUCH OF A RISE IN TEMPS...WITH READINGS IN THE MID 50S LOOKING GOOD...ON TRACK WITH GUIDANCE. FRIDAY NIGHT REMAINS A CHALLENGE AS BEST LIFT WILL BE NORTH OF THE AREA BUT WITH SFC LOW STILL TO OUR IMMEDIATE WEST AND DEEP MSTR STILL IN PLACE...DON'T THINK IT WILL TAKE MUCH TO GET SOME SHOWERS OR AREAS OF RAIN...SO HAVE KEPT LIKELY POPS. THROUGH SATURDAY EVENING...CHC POPS STILL WARRANTED AS LOW BEGINS TO MOVE NORTHEAST ACROSS MICHIGAN AND UPPER LEVEL TROUGH MOVES CLOSER TO THE AREA. 850 MB TEMPS WILL RISE A FEW DEGREES...WHICH WITH SOME BREAKS IN THE CLOUDS EXPECTED...TEMPS SHOULD MAKE IT INTO THE MID-UPR 50S AND POSSIBLY INTO THE 60S. STAYING ON COOLER END OF GUIDANCE FOR NOW DUE TO UNCERTANTITY. PRECIP SHOULD BE CLEAR OF THE AREA BY LATER SATURDAY NIGHT. DRY CONDITIONS WILL PREVAIL WITH MORE SEASONABLE TEMPERATURES EXPECTED ACROSS MUCH OF THE AREA THROUGH WEDNESDAY AS RIDGE TAKES HOLD OVER THE AREA. LATER FORECASTS WILL NEED TO ADDRESS LAKE EFFECT POTENTIAL LATE IN THE WEEKEND AS FAVORABLE DELTA T'S WILL OCCUR...BUT FETCH NOT THE BEST FOR LAKE EFFECT PRECIP OVER THE FAVORED COUNTIES. SOME CONCERNS NOW STARTING TO EVOLVE ON POTENTIAL FOR FIRST SNOWFALL OF THE SEASON IF ECMWF/GEM (AND GFS TO LESSER DEGREE) COME TRUE WITH STRENGTHENING LOW MOVING OUT OF THE GULF STATES...TRACKING OVER CENTRAL OHIO ON WEDS WITH 1000-850 MB THICKNESSES AOB 1530. TOO EARLY TO DEAL WITH IN GRIDS SO STATUS QUO FOR NOW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. && AVIATION/SHORT TERM...HOLSTEN LONG TERM...FISHER $$ in AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 920 AM EST THU NOV 18 2004 .UPDATE... VISIBLE SATELLITE IMAGE SHOWS NUMEROUS BREAKS DEVELOPING IN CLOUD FIELD OVER THE WESTERN AND CENTRAL GREAT LAKES...ESPECIALLY OVER THE NORTHERN PORTION OF THE CWA WHERE SURFACE WINDS ARE BECOMING NORTHWEST IN THE WAKE OF COLD FRONT. ETA20 AND RUC BOTH INDICATE GOOD DRYING BELOW 1000 FT IN WAKE OF COLD FRONT AS WELL AND SURFACE OBS AND SATELLITE SUPPORTING THIS. AS A RESULT FOG AND LOW CLOUD DISSIPATING RAPIDLY...DENSE FOG ADVISORY CANCELLED AT 845 AM AS WELL. ANTICIPATE WIDESPREAD 3-5 MILE VSBYS BY 11 AM. WILL ALSO REMOVE MENTION OF PRECIP AS DRIZZLE HAS DIMINISHED AS LOW CLOUDS LIFT. LIGHT RAIN OVER NORTHERN LOWER SHOULD NOT DRIFT TO MUCH FURTHER SOUTH AS ASSOCIATED UPPER WAVE SHEARS EAST. && GSS .PREV DISCUSSION...ISSUED AT 335 AM WATER VAPOR LOOP THIS MORNING IS QUITE ACTIVE WITH 5 DISTINCT SHORT WAVES (DEPARTING WAVE NOW MOVING EAST OF THE MID-ATLANTIC, OUR LONG LIVED WAVE FROM BAJA CALIFORNIA NOW MOVING ACROSS OKLAHOMA, NEXT WAVE QUICKLY TRACKING EAST FROM LAKE WINNIPEG TOWARD JAMES BAY, AND THE LAST ONE ENTERING THE PACIFIC NORTHWEST COAST. THIS CORRESPONDS TO A RELATIVELY DISORGANIZED UPPER JET FLOW ACROSS NOAM AS JET STREAK FEATURES ARE DIFFICULT TO ASCERTAIN. OUR MAIN PLAYER IS CURRENTLY SITUATED ACROSS OKLAHOMA AND WILL IMPACT OUR REGION IN THE FORM OF RAIN ON FRIDAY. UPSTREAM COOL FRONT IS SCHEDULED TO SLIP SOUTH OF THE STATE LINE DURING THE AFTERNOON HOURS. SURFACE DEWPOINTS BEHIND THIS FRONT DROP BACK TO THE MIDDLE 40S WITH MIDDLE 30S FURTHER BACK INTO WISCONSIN. BUT WILL WE OBSERVE THESE LOWER VALUES ACROSS OUR STATE REMAINS TO BE SEEN. THE AFOREMENTIONED WAVE RACING EAST ACROSS CANADA WILL BE THE KEY PLAYER. THIS WAVE APPEARS TO BE BETTER HANDLED IN THE ETA THIS MORNING WHICH SUGGESTS HEIGHT RISES ACROSS LAKE WINNIPEG AND THE DAKOTAS WILL CONTINUE AND HELP STRENGTHEN THE SURFACE HIGH. WITH THAT SAID, OUR MID LEVEL HEIGHT FIELD BECOMES NEARLY ZONAL WHICH MIGHT STALL THIS FRONT NEAR OR JUST NORTH OF THE STATE LINE THIS AFTERNOON. THERE IS PLENTY OF MOISTURE UPSTREAM AND WITH COMBINATION OF SOUTHERN PLAINS WAVE LIFTING NORTH, WE MIGHT HAVE TO MONITOR THE CHANCES FOR MORE RAIN ACROSS THOSE SOUTHERN COUNTIES. FOR NOW, WE WILL ONLY HAVE MENTION DURING THE MORNING AS DAY CREW WILL MONITOR SHORT TERM TRENDS AND MAKE ADJUSTMENTS IF NEED BE. TEMPS WILL ALSO BE TRICKY AS PLENTY OF CLOUDS AND LOCATION OF THIS FRONT WILL DICTATE WHERE WE WILL OBSERVE 60F. WE WILL BANK ON NEAR 60 SOUTH 1/2 AND UPPER 50S NORTH 1/2. CROSS SECTIONS OVERNIGHT SHOW AN INCREASING EAST WIND AS SURFACE HIGH FROM THE PLAINS STRENGTHENS ACROSS LAKE SUPERIOR WITH PLENTY OF DRY AIR ASSOCIATED WITH IT AND FILTERING SOUTH. MEANWHILE, OUR SOUTHERN SYSTEM BEGINS TO LIFT FURTHER NORTH AND INCREASING IN FORWARD SPEED. PLENTY OF MID-HIGH LEVEL MOISTURE TO KEEP SKIES IN THE MOSTLY CLOUDY TO CLOUDY RANGE (500MB AND UP) WITH LOWER CLOUD DECK FILTERING IN THROUGHOUT THE NIGHT. AGEOSTROPHIC FLOW IN THE 850-700 LAYER INCREASES TO BETWEEN 10-15 KNOTS FROM THE NORTHEAST WHICH WILL NOT ONLY ENHANCE THE DRIER AIR ADVECTING INTO THE REGION BUT INCREASE THE THETA-E GRADIENT UPSTREAM AND FGEN FIELDS. BY FRIDAY MORNING (JUST BEFORE SUNRISE)...WOULD EXPECT RAIN CHANCES INCREASING ACROSS THE FAR SOUTH AND WILL CONTINUE WITH THE CHANCE OF RAIN THERE. FURTHER NORTH, CLOUDS WILL PERSIST AND WITH SOME OF THIS DRIER AIR AT THE SURFACE WE SHOULD BE ABLE TO DROP TEMPS BACK INTO THE LOWER HALF OF THE 40S...PERHAPS SOME UPPER 30S FOR PORTIONS OF BAY-MIDLAND COUNTIES IF DRIER AIR IS DEEP ENOUGH. STRONG ISENTROPIC ASCENT WILL EVENTUALLY OVERCOME THE DRIER LOWER LEVELS AND WITH PRECIPITABLE WATERS CLIMBING TOWARD 1" (WHICH IS OVER 200% OF NORMAL)...RAIN WILL SPREAD FROM SOUTH TO NORTH THROUGHOUT THE DAY FRIDAY. IT MAY TAKE ALL DAY FOR THE NORTHERN 1/3RD OF THE CWA AND WE WILL HOLD ONTO THE HIGH CHANCE THERE. WEAK SURFACE LOW ASSOCIATED WITH THE UPPER SYSTEM (1010MB) WILL TRACK ACROSS THE WESTERN LAKES WITH OCCLUDED FRONT HEADING NORTH ACROSS THE STATE FRIDAY NIGHT. IMPRESSIVE DEEP THETA-E RIDGE OVERHEAD WILL RESULT IN OCCASIONAL LIGHT RAIN/DRIZZLE/FOG AND TEMPERATURES EITHER HOLDING STEADY OR SLOWLY RISING OVERNIGHT. STILL RETAIN THE CHANCE FOR SHOWERS ON SATURDAY BUT MODEL MOISTURE FIELDS ARE TRENDING TOWARD DRIER CONDITIONS (IE NOT NEARLY AS DEEP IN THE MOISTURE PROFILES)...BUT STILL PLENTY OF CLOUDS AROUND. WE ARE STILL ON TAP FOR A RETURN TO COOLER WEATHER ALONG WITH RAIN AND SNOW SHOWERS. TIMING OF INDIVIDUAL WAVES IS ALWAYS PROBLEMATIC AND LAKE CONTRIBUTION INFLUENCES. BUT WOULD EXPECT ALL OF THE REGION TO SEE SOME SNOW FALLING THE WEEK OF THANKSGIVING. && .DTX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ BGM EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 935 PM CST THU NOV 18 2004 .DISCUSSION... -RA ASSOCD WITH FIRST S/W TROF IN SRN IA ROTATING AROUND UPR LOW SPREADING SLOWLY NWD INTO SOUTH CENTRAL MN. BOTH ETA AND GFS SHOW PRECIPTABLE WATER VALUES INCREASING BY ONE QUARTER INCH DURING THE LATE NIGHT ACRS CENTRAL MN...AND 295-300 THETA SHOWING FROM BOTH RUC AND ETA SHOWING CONDENSATION PRES DEFICITS DECREASING TO LESS THAN 10MB WITH 10 TO 20MB LIFT...HWVR ISENTROPIC OMEGA NOT THAT STRONG. BETTER LIFT DEVELOPS FRI MRNG AS KS SYSTEM EJECTS NEWD. HAVE ALREADY UPDATED ZFP AND GRIDS TO REFLECT OCNL WORDING IN SOUTH AND EXPANDING LKLY AND CHC POPS ONE TO TWO TIERS NWD INCLUDING MSP METRO. SOME WORRY OF BRIEF PERIOD OF MIX PRECIP IN WESTERN CWA LATE TNGT AND EARLY FRI. TEMPERATURES NEAR FREEZING WITH DEWPTS IN THE MID 20S...PLUS THIS AREA VERY DRY...SO EVAPORATIVE COOLING MAY RESULT IN MIXTURE OR -ZR. && MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ MBK mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON MS 915 PM CST THU NOV 18 2004 .DISCUSSION...LATEST SFC ANALYSIS HAS A WEAK CENTER OF LOW PRESSURE JUST EAST OF ESLER REGIONAL AIRPORT(ESF). THIS FEATURE IS EXPECTED TO DRIFT SLOWLY EAST OVERNIGHT. THE RUC40 IS A LITTLE SLOWER THAN THE ETA40 WITH THE MOVEMENT EAST...THIS WOULD DELAY THE DRIER WEST WINDS AND RESULT HIGHER MORNING MINIMUM TEMPERATURES IN OUR SOUTHWEST PARISHES AND COUNTIES THAN CURRENT FORECAST SUGGESTS. WL RAISE MINIMUM TEMPERATURES A FEW DEGREES IN THE SOUTHWEST. LOCAL RADARS INDICATE THAT THE BACK EDGE OF THE SIGNIFICANT RAINFALL IS ALONG AND EAST OF THE RIVER. THIS EDGE WILL SHIFT TO THE EAST AND WL REDUCE POPS IN THE WEST AFTER MIDNIGHT. UPDATED GRIDS ALREADY PUBLISHED. WL UPDATE ZONES SHORTLY. && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 22-MME ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 930 AM EST THU NOV 18 2004 .SHORT TERM (THIS AFTERNOON)... IN WATER VAPOR THIS MORNING LOW / VORT MAX CENTERED TO THE NORTHEAST OF CWA AND EXPECTED TO PASS OFF TO OUR EAST THIS AFTERNOON. RADAR SHOWING A FEW SPRINKLES APPROACHING NORTHERN AREAS. KCTZ IS REPORTING LIGHT RAIN. WILL ADD ISOLATED LIGHT RAIN TO THE AFTERNOON FORECAST BUT AS LIFT AND CLOUDS QUICKLY MOVE ON IT WILL BE OVER EARLY. && .AVIATION... EXCEPT FOR SOME TEMPO MVFR VISIBILITIES FROM 12-14Z, TERMINALS EXPECTED TO REMAIN VFR THROUGH 19/12Z. A WELL DEFINED VORT MAX IN SOUTHEAST VIRGINIA IS MOVING SOUTHEAST, SPREADING AN EXTENSIVE 6K CLOUD DECK ALONG WITH IT. THIS CLOUD DECK IS EXPECTED TO PERSIST AT FLO THROUGH 19/12Z, WHILE SOME SCATTERING OF THIS CLOUD DECK IS POSSIBLE FOR THE COASTAL TERMINALS AFTER 20Z AS VORT PASSES AND STRONGEST NVA SETTLES IN. WITH THE CLOUD DECK PERSISTING JUST TO THE WEST OF THE COASTAL TERMINALS, SOUTHWEST TO WEST FLOW AT 85H AFTER 19/00Z SHOULD ALLOW CLOUD DECK TO ADVECT BACK EAST INTO THE COASTAL TERMINALS, WHERE IT WILL PERSIST THROUGH 19/12Z. && .MARINE... LIGHT WINDS OVER THE WATERS AND 12Z RUC CONTINUE TO SHOW WINDS LESS THAN 10 KNOTS BUT WITH A SLIGHT VEERING THROUGH THE EVENING. STILL SEEING A 2.5 FT SWELL OVER THE WATERS SO MAY TWEAK SEA UP A 1/2 FOOT FOR THE AFTERNOON. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...NONE. SC...NONE. MARINE...NONE. && $$ SHORT TERM...HAWKINS AVIATION...MR MARINE...HAWKINS nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 350 AM EST FRI NOV 19 2004 .DISCUSSION... 00Z RAOBS/WATER VAPOR LOOP SHOW UPPER TROUGH OVER THE CENTRAL PLAINS/MID-MISSISSIPPI VALLEY...WITH A SHORTWAVE RIDGE ACROSS THE WESTERN/SOUTHERN GREAT LAKES. OTHERWISE A NUMBER OF ADDITIONAL SHORTWAVES UPSTREAM...ACROSS THE NORTHERN/SOUTHERN HIGH PLAINS AND WEST COAST. SURFACE ANALYSIS SHOWS WEAK WAVE OVER EASTERN KANSAS/NEBRASKA...WITH A FRONT EXTENDING OUT THROUGH THE NORTHERN OHIO VALLEY. HIGH PRESSURE CONTINUES TO BUILD EASTWARD ACROSS THE NORTHERN GREAT LAKES/NORTHERN ONTARIO. REGIONAL RADARS SHOW WIDESPREAD PRECIP FROM LOWER MICHIGAN DOWN THROUGH SOUTHERN ILLINOIS/INDIANA. MAIN FORECAST ISSUE IS WITH PRECIP COVERAGE/DURATION TODAY/TONIGHT. ETA/GFS CONTINUE TO BE PRETTY SIMILAR INITIALLY WITH THE OVERALL TIMING OF THE MID MISSISSIPPI VALLEY LOW...LIFTING IT NORTHEAST THROUGH THE WESTERN GREAT LAKES...EVENTUALLY DEEPENING/MERGING WITH THE NORTHERN STREAM SYSTEM MOVING THROUGH SOUTHERN CANADA. ETA/GFS THEN DIVERGE BY THE END OF THE WEEKEND THOUGH...WITH RESPECT AS TO HOW THE NEXT SOUTHWESTERN LOW WILL DEVELOP. GFS IS MORE CUTOFF WITH THE LOW...WHILE THE ETA TRIES TO KEEP THE PATTERN MORE PHASED AND PROGRESSIVE. WILL LEAN TOWARD THE SLOWER GFS SOLUTION...WHICH IS THE PATTERN THAT SEEMS TO HAVE BEEN MORE FAVORED THIS FALL. 00Z CANADIAN GLOBAL ALSO SUPPORTS THIS SOLUTION. FOR TODAY...WILL RELY MORE ON AN EXTRAPOLATION OF CURRENT RADAR CONDITIONS AS MODELS STILL DO NOT HAVE A GOOD HANDLE ON THE EXTENT OF PRECIP COVERAGE. EVEN THE 06Z RUC DOES NOT BRING PRECIP INTO CENTRAL LOWER MICHIGAN UNTIL LATE MORNING...WHILE KLAN HAS REPORTED LIGHT RAIN SINCE 07Z. WE ARE SEEING STRONGER THETA-E ADVECTION WITH THIS INITIAL SURGE OF MOISTURE...WHICH IS WORKING TO QUICKLY OVERCOME THE 20C DEWPOINT DEPRESSIONS OBSERVED ON THE 00Z DTX SOUNDING. WHILE IT MAY NOT HAVE A GOOD HANDLE ON THE NORTHWARD EXTEND OF PRECIP INITIALLY...THE ETA DOES SEEM TO OFFER A REASONABLE SOLUTION WITH A SHARP CUTOFF TO PRECIP DUE TO DRY ADVECTION AROUND THE SURFACE HIGH BUILDING ACROSS NORTHERN ONTARIO. DETERMINING WHERE THIS NORTHERN EDGE SETS UP WILL BE TRICKY. BASED ON CURRENT RADAR TRENDS AND TIMING...WILL START OUT WITH CATEGORICAL POPS MORE AREAS EXCEPT FOR THE NORTHERN THUMB. SHORTWAVE RIDGE SHIFTS DOWNSTREAM TO THE LOWER GREAT LAKES BY THIS EVENING...WHICH SHOULD BE ENOUGH TO ALLOW PRECIP TO SPREAD A LITTLE FARTHER NORTH DURING THE AFTERNOON. 00Z MODELS DO NOT INDICATE MUCH FOCUSED LIFT THROUGH THE DAY BEHIND THE INITIAL SURGE OF WARM/MOIST ADVECTION EARLY THIS MORNING... HOWEVER WITH ABUNDANT MOISTURE AND PRECIP OBSERVED WELL BACK TO THE SOUTHWEST ALREADY...WILL STICK WITH CATEGORICAL POPS THROUGH THE DAY. AS FOR HIGHS TODAY...EXPECT A RATHER SMALL DIURNAL CLIMB GIVEN AMOUNT OF CLOUD COVER AND PRECIP ACROSS THE AREA. LITTLE CHANGE IN THE SOURCE AIRMASS COMPARED TO YESTERDAY /HIGHS IN THE LOW 60S/...HOWEVER A SOLID AND DEEP CLOUD DECK AND STRENGTHENING INVERSION DUE TO ELEVATED WARM ADVECTION WILL KEEP TEMPS IN CHECK. UPPER SHORTWAVE LIFTS TO WISCONSIN/LAKE MICHIGAN BY 12Z SATURDAY... LEADING TO SOME ADDITIONAL SURFACE CYCLOGENESIS...HELPING TO PROPEL THE SURFACE FRONT NORTHWARD THROUGH THE CWA AS A WARM FRONT. WITH ABUNDANT MOISTURE AND WEAK LIFT WILL CONTINUE WITH CATEGORICAL POPS TONIGHT ACROSS THE CWA. PRECIP MAY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE SOUTHERN CWA BEHIND THE FRONT. HOWEVER WILL HOLD ON TO CATEGORICAL POPS FOR LIGHT RAIN THROUGH THE NIGHT GIVEN PERSISTENT WEAK LIFT AHEAD OF THE SYSTEM. AS WAS THE CASE WITH TODAY...DO NOT EXPECT MUCH OF A DIURNAL TEMPERATURE SWING GIVEN AMOUNT OF LOW-LEVEL MOISTURE AND CLOUDS...IN ADDITION TO OUR PLACEMENT IN THE WARM SECTOR. WITH AMOUNT OF LOW-LEVEL MOISTURE /SURFACE CONDENSATION PRESSURE DEFICITS BELOW 10MB/...FOG MAY BE A CONCERN. GRADIENT REMAINS UP IN ADDITION TO CLOUDS AND PRECIP SO WILL JUST MENTION AREAS OF FOG IN THE PUBLIC FORECAST AT THIS POINT. HOWEVER IF PRECIP ENDS DURING THE NIGHT AND LOW-LEVEL MOISTURE FLUX CONTINUES...COULD SEE CLOUDS BUILD DOWN TO THE SURFACE FOR MORE OF A VISIBILITY PROBLEM. AT THIS POINT UPSTREAM...IFR CLOUDS AND VISIBILITY ONLY DOWN TO 1SM LOOK MOST COMMON. DEEPENING SURFACE WAVE MOVE THROUGH THE NORTHERN GREAT LAKES SATURDAY/SATURDAY NIGHT...FOLLOWED BY A SURFACE HIGH BUILDING DOWN INTO THE PLAINS/WESTERN GREAT LAKES. SOME MID-LEVEL DRY ADVECTION ON SATURDAY AND ESPECIALLY SATURDAY NIGHT...ALTHOUGH WEAK SYNOPTIC LIFT CONTINUES UNTIL THE NORTHERN STREAM TROUGH SHIFTS DOWNSTREAM SATURDAY NIGHT. WILL HOLD ONTO HIGH CHANCE POPS SATURDAY WITH LINGERING MOISTURE AND LIFT...AND LOW CHANCE POPS SATURDAY NIGHT UNTIL MOISTURE STARTS TO CLEAR AWAY. AS MENTIONED ABOVE...ETA/GFS DIVERGE HEADING INTO THE LATE WEEKEND. WITH THE PREFERRED GFS SOLUTION...UPPER LOW LINGERS LONGER ACROSS THE SOUTHWEST...AND DOES NOT PHRASE AS MUCH WITH THE NEXT NORTHERN STREAM WAVE. THIS ALLOWS A SURFACE HIGH TO BUILD INTO THE OHIO VALLEY BY F84/12Z MONDAY UNDER GENERALLY CONFLUENT UPPER FLOW. ETA IS NOTICEABLY DIFFERENT AT THE SURFACE WITH AN INVERTED TROUGH ACROSS GENERALLY BETWEEN THE MISSISSIPPI AND APPALACHIANS...DUE TO MORE SOUTHWESTERLY UPPER FLOW BETWEEN THE PHASED SYSTEMS. PREFER THE GFS...AND WILL KEEP A DRY FORECAST SUNDAY/MONDAY. SOUTHWESTERN LOW THEN EJECTS INTO THE SOUTHERN PLAINS ON TUESDAY...LEADING TO A BETTER MOISTURE RETURN AND OUR NEXT CHANCE FOR PRECIP. CURRENT GFS IS FASTER EJECTING THIS SYSTEM THAN THE 00Z RUN YESTERDAY...AND ALSO TAKES IT ON A MORE WESTERLY TRACK. CONSEQUENTLY THE CURRENT GFS IS MUCH WARMER THAN EARLIER RUNS. TWEAKED PRECIP TYPE ON TUESDAY A BIT...ALTHOUGH NOT TOO MUCH BEYOND THAT GIVEN UNCERTAINTY ASSOCIATED WITH THIS SYSTEM. && .DTX WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY...THIS AFTERNOON AND TONIGHT...OUTER SAGINAW BAY AND LAKE HURON NEARSHORE. && $$ BRAVENDER EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 242 AM EST FRI NOV 19 2004 .DISCUSSION... MAIN FORECAST CONCERN IS WITH SHORTWAVE CURRENTLY OVER WESTERN NEBRASKA AND THE SURFACE LOW IT WILL HELP TO DEVELOP AND BRING OUR WAY OVER THE NEXT 24-36 HOURS. THE LATEST WATER VAPOR IMAGERY AND RUC UPPER AIR ANALYSES SHOW THIS SHORTWAVE NICELY...AS WELL AS ADDITIONAL SOUTHERN STREAM SHORTWAVES OVER NEW MEXICO AND FAR WESTERN KENTUCKY. NORTHERN STREAM SHORTWAVES CONTINUE TO RIPPLE ALONG THE US/CANADA BORDER...WITH A FAIRLY VIGOROUS WAVE CURRENTLY ALONG THE MONTANA/ALBERTA BORDER. ALTHOUGH THIS NORTHERN WAVE WILL HAVE SOME IMPACT ON OUR WEATHER OVER THE NEXT SEVERAL DAYS...THE SHORTWAVE OVER NEBRASKA IS THE MAIN FEATURE WHICH WILL HELP TO BRING PCPN NORTH INTO THE CWFA TONIGHT. THE 00Z ETA AND GFS ARE IN DECENT AGREEMENT OVERALL...ALTHOUGH THE ETA IS A BIT FASTER IN THE PROGRESSION OF FEATURES THROUGH THE PERIOD. WILL UTILIZE A BLEND OF THEIR GUIDANCE...WHICH STILL RESULTS IN SPEEDING THINGS UP SLIGHTLY THROUGH SUNDAY. PCPN SHIELD CURRENTLY TO OUR SOUTH IS HAVING A TOUGH TIME MOVING NORTH INTO THE DRY AIR CURRENTLY IN PLACE ACROSS THE REGION...WITH ONLY SOME SPRINKLES AND VERY LIGHT RAIN TAKING PLACE BENEATH THE RADAR ECHOES OVER SOUTHERN WISCONSIN. SOUTHERLY FLOW WILL INCREASE THROUGH THE DAY AS THE SHORTWAVE LIFTS NORTHEAST FROM THE PLAINS...WHICH WILL HELP TO MOISTEN THINGS UP AND BRING PCPN NORTH AS THE DAY PROGRESSES. UNTIL THAT HAPPENS...HOWEVER...LOOK FOR MID-LEVEL FRONTOGENESIS AT THE LEADING EDGE OF WAA TO CONTINUE TO DO LITTLE MORE THAN THICKEN THE AC DECK. THIS AREA OF MID-LEVEL FRONTOGENESIS MAKES IT INTO OUR AREA BY MID TO LATE AFTERNOON...SO THERE IS SOME CHANCE FOR PCPN TO MAKE IT INTO THE SOUTHWEST CWFA BY LATE AFTERNOON...BUT THE BETTER CHANCES SHOULD HOLD OFF UNTIL THIS EVENING WHEN LOW LEVEL WINDS VEER MORE SOUTHERLY AND HELP SATURATE THE LOW LEVELS. THE SHORTWAVE IS EXPECTED TO MOVE NORTHEAST ACROSS THE CWFA LATE TONIGHT AND DURING THE MORNING ON SATURDAY...HELPING TO LIFT THE SURFACE LOW NORTHEAST ACROSS THE CWFA. ALTHOUGH SOME UPPER DIVERGENCE IN THE LEFT EXIT REGION OF THE UPPER JET ASSOCIATED WITH THE SHORTWAVE WILL AID IN FORCING TONIGHT...THE BULK OF LIFT WILL COME VIA ISENTROPIC ASCENT WHICH IS DEPICTED NICELY ON THE 295K SURFACE. WITH THE NORTHERN STREAM SHORTWAVE A BIT TOO FAR WEST AND NORTH TO INTERACT WITH THE SOUTHERN SHORTWAVE...AM NOT EXPECTING ANY COUPLED JET DYNAMICS OR BOOST TO THE FORCING FROM THE SOUTHERN WAVE. USING THE 295K THETA SURFACE DEPICTION OF CONDENSATION PRESSURE DEFICITS AND ADIABATIC OMEGA...ONE WOULD EXPECT TO SEE PCPN WORK INTO THE SOUTHWEST CWFA BY EARLY THIS EVENING...THEN SPREAD NORTHEAST ACROSS THE REMAINDER OF THE AREA THROUGH THE EVENING HOURS. MID-LEVEL MOISTURE LOOKS LIKE IT WILL DEPART FAIRLY QUICKLY ON SATURDAY...WITH THINGS DRYING OUT FROM SOUTHWEST TO NORTHEAST DURING THE LATE MORNING AND EARLY AFTERNOON. LOW LEVEL ISENTROPIC DOWNGLIDE WILL ALSO KICK IN DURING THE MORNING HOURS...WHICH WILL FURTHER HELP TO BRING PCPN TO AN END. WILL ALLOW FOR A CHANCE OF SHOWERS TO PERSIST FROM SATURDAY AFTERNOON INTO THE OVERNIGHT HOURS...WITH A MENTION OF RAIN/SNOW AFTER MIDNIGHT AS 1000-850MB THICKNESSES DROP BELOW 1300M. HOWEVER...PROGGED INSTABILITY IS VERY MARGINAL AS ARE INVERSION HEIGHTS...SO WILL ONLY GO WITH LOW CHANCE POPS. THE LOW LEVEL THERMAL TROUGH IS PROGGED TO MOVE EAST OF THE CWFA ON SUNDAY...ALLOWING BOUNDARY LAYER RH TO FALL. IN ADDITION...BOUNDARY LAYER WINDS ARE EXPECTED TO BACK THROUGH THE DAY AND BECOME SLIGHTLY SOUTH OF WEST BY EVENING...SO WILL END ANY CHANCE OF SNOW SHOWERS SUNDAY AFTERNOON. RETURN FLOW BEGINS TO SETUP ON MONDAY...WITH SHORTWAVE RIDGING OVER THE AREA...SO WILL REMOVE ANY MENTION OF PCPN FROM THE FORECAST. THINGS LOOK POTENTIALLY INTERESTING AS WE HEAD INTO THE MIDDLE PART OF THE WEEK...WITH THE ECMWF HINTING AT A POTENTIAL STORM MOVING INTO THE WESTERN GREAT LAKES. THE GFS AND CANADIAN ARE EAST OF THE ECMWF WITH RESPECT TO THE TRACK OF THIS STORM...BUT IT WILL BE SOMETHING ON WHICH TO KEEP AN EYE. LATER SHIFTS CAN FURTHER EVALUATE THE AVAILABLE GUIDANCE...AND MAKE CHANGES TO THE FORECAST BEYOND MONDAY IF NEEDED. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ TRH mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 251 AM EST FRI NOV 19 2004 .SYNOPSIS... HI PRESS TO BUILD IN ACRS THE FA FROM THE NW TODAY AND TONITE. STORM SYS TO MOVE ACRS THE GREAT LKS REGION ON SAT AND SRN CANADA ON SAT NITE. CF TO MOVE ACRS THE FA ON SUN/SUN NITE. S/W TO MOVE ACRS THE FA ON SAT NITE. .SHORT TERM (THROUGH SUN NITE)... 00-03Z 13KM "DEVELOPMENT" RUC SHOWS TEMPS TO BE IN THE U30S-M40S TODAY WITH NORTHWESTERLY SFC WINDS AT 5-15 KTS. T1MAX TEMPS ARE IN THE L40S-M50S TODAY. RUC INDICATING THAT TEMPS MAY ACTUALLY TAKE A TUMBLE THROUGHOUT THE DAY TODAY. FEW TWEAKS TO FIRST PERIOD TEMPS/WINDS BASED ON THIS DATA AND CURRENT MESONET OBS. RUC SHOWS LOW-LVLS TO DRY OUT TODAY...BUT IT ALSO HANGS ONTO MOCLDY SKIES FOR TODAY ACRS THE FA. PW VALUES ACRS THE FA TO DROP TO BLO 0.5" TODAY. BUFCAN/88D MOSAIC SHOW SOME VERY LT RETURNS ACRS THE FA ATTM. IR SAT PIX SHOW THE LEADING EDGE OF THE CLEARING LINE JUST ENTERING THE ST LAW VLY ATTM. H85 CAA TO TAKE PLACE ACRS THE FA TODAY AND TONITE...THEN WAA TO DEVELOP ACRS THE FA FOR SAT AND SAT NITE...AND CAA TO REDEVELOP ON SUN/SUN NITE. H925 WET-BULB TEMPS TO GO NEGATIVE ACRS THE FA BY AROUND 00Z SAT...THEN POSITIVE BY AROUND 18Z SUN AND NEGATIVE AGAIN BY AROUND 12Z MON. MUCH OF THE LATEST THICKNESS AND ETA BUFR DATA SEEM TO SUPPORT ALL RAIN ACRS THE FA DURING THE SHORT-TERM PERIOD THOUGH (EXPECT MAYBE IN THE HIR TRRN ON SUN NITE?). LOW-LVL MSTR ADVECTION TO TAKE PLACE ACRS THE ON SAT AND SAT NITE. LOW-LVL MSTR TO INCREASE ACRS NY STATE LATE ON SAT AND AFFECT THE ENTIRE FA ON SAT NITE THROUGH MUCH OF SUN NITE. LOW-LVL LAPSE RATES TO BE HI ACRS THE FA ON SUN NITE. MID-LVL MSTR TO INCREASE ACRS THE FA LATE ON SAT AND INTO SAT NITE AND EARLY ON SUN. PW VALUES ACRS THE FA LOOK TO BE AROUND 0.5" ON SAT AND SUN NITE...AROUND 0.75" ON SAT NITE...AND 0.5-0.75" ON SUN. WILL CONT TO GO WITH SOME CLEARING ACRS MUCH OF THE FA TODAY AND WILL MOST LIKELY HANDLE ANY LINGERING PCPN/FG ACRS THE FA WITH THE STF. WOULD PREFER TO WAIT FOR THE COMPLETE PASSAGE OF THE UPR RIDGE ACRS THE FA BEFORE BRINGING ANY SIGNIFICANT PCPN INTO THE WRN FA LATE ON SAT...SO WILL HANG ONTO SCHC POPS FOR THERE FOR NOW. BEST CHC FOR ANY PCPN IN THE SHORT-TERM PERIOD LOOKS TO BE ON SAT NITE (WHERE LIKELY POPS WILL BE USED)...WITH LESSER CHCS AS SUN AND SUN NITE PROGRESS. LATER SHIFTS WILL NEED TO KEEP AN EYE ON THE P-TYPE ISSUE THOUGH. T1MIN TEMPS ARE MOSTLY IN THE 20S TONITE AND IN THE 30S ON SAT NITE. T1MAX TEMPS ARE MOSTLY IN THE 40S ON SAT. .LONG TERM (MON ONWARD)... NO CHANGES TO THE GOING FCST FOR NOW. PRELIM WRK ZONES AND ISC GRIDS AVAILABLE. ALL FINAL PRODUCTS BY AROUND 330 AM. MURRAY .AVIATION... AREAS OF MVFR CONDITIONS WITH LOCAL IFR WL PERSIST THRU ABOUT MID MORNING...THEN GRADUAL LIFTING OF CIGS WITH SCT CLDS/VFR CONDS DVLPG BY 18Z AS LOW LVL MSTR DECREASES. VFR TNGT WITH A FEW HI CLDS...OTRW SKC. N TO NW WINDS WL INCREASE TO 10-15 KTS BY MID MRNG... THEN BECOME LIGHT TNGT. KJC .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 255 AM CST THU NOV 18 2004 .SHORT TERM...THROUGH SUNDAY MAIN CONCERN IS WITH PRECIPITATION CHANCES INTO SATURDAY. SURFACE ANALYSIS EARLY THIS MORNING INDICATES HIGH PRESSURE IS CENTERED JUST NORTH OF THE MINNESOTA ARROWHEAD. LOW PRESSURE WAS ALONG THE NEBRASKA/KANSAS STATE LINE WEST OF KFNB. A WARM FRONT EXTENDED EAST FROM THE LOW ACROSS SOUTHERN IOWA INTO CENTRAL ILLINOIS. LOCAL AND REGIONAL RADARS INDICATING A LARGE AREA OF MAINLY LIGHT RAIN OCCURRING NORTH OF THE FRONT. 00Z MODELS SHOW GOOD AGREEMENT WITH THE MASS FIELDS. WITH THE PRECIPITATION EVENT ONGOING AND CONTINUING INTO THE EARLY PART OF THE FORECAST...HAVE RELIED ON THE HIGHER RESOLUTION OF ETA FOR ANY FINE TUNING. SHORT WAVE TROUGH IN THE LEE OF THE ROCKIES EARLY THIS MORNING WILL MOVE SLOWLY NORTHEAST ACROSS THE UPPER MIDWEST TODAY AND TONIGHT. ANOTHER SHORT WAVE TROUGH OVER THE PACIFIC NORTHWEST THIS MORNING WILL MOVE INTO THE UPPER MIDWEST LATE TONIGHT HELPING TO ESTABLISH A LONG WAVE OVER THE REGION. THESE TWO SHORT WAVE TROUGHS WILL COMBINE TO KEEP A PROLONGED PERIOD OF VORTICITY ADVECTION AND UPWARD VERTICAL MOTION OVER THE AREA. TIME/HEIGHT PLOTS SHOW THIS SYNOPTIC SCALE LIFT SHOULD BE ON THE ORDER OF 3 UBAR/S THROUGH MUCH OF THE DAY INTO THE EVENING. THIS SYNOPTIC SCALE LIFT WILL BE AIDED BY LOW LEVEL WARM AIR ADVECTION NORTH OF THE WARM FRONT WITH UP TO 2 UBAR/S OF UPWARD MOMENTUM ON THE 290K ISENTROPIC SURFACE. PREVIOUS FORECAST ALREADY HAD RAISED POPS TO 100 PERCENT FOR THE DAY AND SEE NO REASON TO MAKE ANY CHANGES TO THIS. SYNOPTIC SCALE AND ISENTROPIC LIFT WILL CONTINUE THROUGH THE EVENING TONIGHT BUT THEN START TO SHIFT EAST AS THE LONG WAVE TROUGH APPROACHES PUSHING EVERYTHING TOWARD THE GREAT LAKES. THE SURFACE LOW IS EXPECTED TO TRACK FROM SOUTHEAST MINNESOTA AT 06Z SATURDAY INTO NORTHEAST WISCONSIN BY 12Z SATURDAY. WITH THE MODELS NOT SHOWING ANY ISENTROPIC LIFT...FRONTOGENESIS OR QG CONVERGENCE ON THE BACK SIDE OF THE LOW...WILL LEAVE THE POPS AT 100 FOR THE EVENING AND THEN START TO SCALE BACK ACROSS THE WEST AFTER 06Z SATURDAY. THE NEW 06Z RUN OF THE ETA AND THE 00Z RUN OF THE RUC13 INDICATE THAT MOST OF THE RAIN MAY BE EAST OF THE FORECAST ALREADY AROUND 12Z SATURDAY. OPTED TO LEAVE THE HIGH POPS ACROSS THE NORTHEAST THROUGH THE FIRST HALF OF SATURDAY MORNING BUT THEN SCALE BACK TO CHANCE BETWEEN 15 AND 18Z AND CONTINUE THE TREND OF HAVING ALL THE RAIN EAST OF THE FORECAST AREA AFTER 18Z SATURDAY. IF CURRENT MODEL TRENDS CONTINUE...LATER SHIFTS MAY HAVE TO MOVE UP OF THE TIMING OF PUSHING THE RAIN TO THE EAST. TEMPERATURE TRENDS FROM THE PREVIOUS FORECAST CYCLE THROUGH SUNDAY LOOKED GOOD AND ONLY MADE SOME MINOR TWEAKS. .LONG TERM...SUNDAY NIGHT THROUGH THURSDAY LATEST RUN OF THE GFS INDICATES THAT ONCE THE LONG WAVE TROUGH MOVES INTO THE GREAT LAKES REGION SUNDAY...WEAK UPPER LEVEL RIDGING WILL BUILD OVER THE UPPER MIDWEST. THIS RIDGE IS THEN INDICATED TO BREAK DOWN MONDAY NIGHT AS THE NEXT SYSTEM CROSSES THE ROCKIES WITH A NORTHERN STREAM SHORT WAVE TROUGH PHASING WITH A CUT OFF LOW IN THE SOUTHERN STREAM. THE COMBINATION OF THESE TWO SYSTEMS MAY BRING SOME PRECIPITATION TO MUCH OF THE FORECAST AREA FOR MONDAY NIGHT INTO TUESDAY. CURRENT FORECAST DATABASE ONLY HAS LOW CHANCE POPS ACROSS THE NORTH AND MODEL TRENDS CONTINUE THESE MAY NEED TO BE EXPANDED TO THE SOUTH AND BUMPED UP. && .ARX...WATCHES/WARNING/ADVISORIES... IA...NONE. WI...NONE. MN...NONE. && $$ 04 wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 836 AM EST FRI NOV 19 2004 .DISCUSSION...A SHORT WAVE IS LIFTING NE ACROSS THE LOWER OHIO VALLEY THIS MORNING. THIS HAS HELPED TO FLATTEN THE UPPER RIDGE, WITH ZONAL FLOW NOW IN PLACE ACROSS THE GULF COAST STATES. SURFACE ANALYSIS SHOWS THAT A WEAK WAVE OF LOW PRESSURE HAS FORMED OVER THE N CENTRAL GULF AT THE TRIPLE POINT OF THE PARENT FRONTAL SYSTEM. WARM FRONTOGENESIS IS OCCURRING OVER OUR COASTAL WATERS. AREA VAD WIND PROFILES SHOW WARM ADVECTION ONGOING OVER THE AREA. RUC ANALYSES INDICATES DECENT ISENTROPIC ASCENT ON THE 295 K SURFACE W OF THE AREA OVER AL, AND REGIONAL RADARS SHOW THAT THIS IS EXACTLY WHERE THE MOST SOLID AREA OF PRECIPITATION IS LOCATED. THE RUC FORECASTS THIS AREA TO MOVE E THROUGH THE DAY TODAY. THE GFS ALSO SHOWS THIS AT 300 K. THE OVERRUNNING IS WEAKER FURTHER E OVER OUR AREA THIS MORNING, BUT THE RADARS SHOW PATCHES OF LIGHT RAIN MOVING E ACROSS THE FORECAST AREA. SEVERAL AREA METARS HAVE ALREADY RECORDED MEASURABLE PRECIP. THE 12Z KTLH SOUNDING SHOWS SIGNIFICANT MOISTENING OVER THE LAST 12 HOURS BELOW 550 MB, WITH THE PW UP TO 1.33 INCHES. && .UPDATE...ALL OF THE ABOVE NECESSITATES UPDATING THE PUBLIC FORECAST TO RAISE POPS SIGNIFICANTLY. WILL ALSO GO MORE PESSIMISTIC WITH CLOUD COVER. THIS SILL KEEP TEMPS DOWN, ESPECIALLY W. WE PLAN TO GO WITH THE HIGHER POPS AND LOWER TEMPS OF THE 06Z MAV. && .MARINE...THE GRADIENT E OF THE SURFACE LOW HAS TIGHTENED MORE THAN ANTICIPATED AND EXERCISE CAUTION CONDITIONS HAVE BEEN OBSERVED AT BUOY 42039 FOR THE LAST SEVERAL HOURS. WE ISSUED AN EARLY UPDATE TO COVER THIS. NONE OF THE MODELS IS DEPICTING THE SURFACE LOW ALL THAT WELL. && .FIRE WEATHER...NO CONCERNS FOR THE NEXT SEVERAL DAYS. && .PREV DISCUSSION... 215 AM EST FRI NOV 19 2004 THE UPPER RIDGE HAS MOVED TO THE EAST COAST...AS THE UPPER TROUGH & SYSTEM MAKING PROGRESS NE-E TO THE OH VALLEY. OMEGA & VORT LOBE SOUTH OF LOW TO N FL SPREADING LIGHT RAIN TO PARTS OF CWA. COVERAGE & INTENSITY LOW. AT THE SURFACE...RIDGING PATTERN STILL HOLDING FROM THE CAROLINAS SW TO N FL...WITH WEAK BOUNDARY OVER LA-AR. STRONG THETA-E GRADIENT SEEN FROM COASTAL WATERS OFF N FL...NW TO LOWER MS VALLEY. THIS MOISTURE INFLUX SOURCE A BIT LIMITED & OVER COMING IN PLACE DRY AIRMASS. 00Z TLH SOUNDING HAD A PRECIP WATER VALUE OF 0.63 INCHES WITH LIGHT E-SE FLOW. ATMOSPHERE REMAINS QUITE STABLE OVER CWA...SO LIGHT RAIN/SHOWERS ONLY SEEN & EXPECTED. WITH CLOUDS OVER REGION...LOWS MILDER THIS MORNING. SHORT TERM...TODAY THROUGH SUNDAY. MODELS HAVE SURFACE BOUNDARY MAKING SOME PROGRESS EAST TO MS VALLEY...BUT STALL IT IN THAT AREA. OMEGA & VORT LOBE PUSHES ACROSS AL/GA/N FL TODAY WITH CURRENT CHANCE OF LIGHT RAIN/SHOWERS. ON SATURDAY WEAK BOUNDARY SAGS A BIT FAR EAST TO AROUND GA TO N FL. SOME OMEGA LIFT AGAIN SWEEPS ACROSS CWA WITH CHANCE OF MAINLY RAIN/SHOWERS. MAINLY STABLE CONDITIONS TODAY...A BIT OF INSTABILITY FOR SATURDAY WITH LI 0 TO -2 INTO THE CWA...AN ISOLATED TSTM POSSIBLE BUT STILL MAINLY RAIN/SHOWERS. SUNDAY THE BOUNDARY DRIFTS A BIT NORTH WITH BETTER SOUTH FLOW OVER THE CWA...& MORE OMEGA LIFT SWEEPS ACROSS AL/GA & CLOSE TO N FL. CHANCE POPS TO SLIGHT POSSIBLE. LONG TERM...SUNDAY NIGHT THROUGH THANKSGIVING DAY. GFS SUGGESTS BOUNDARY TO PUSH SOUTH A BIT ON MONDAY WITH SOME DRYING & A NE FLOW BACK TO MOST OF THE CWA...& WITH LOWER CHANCES OF RAIN. THEN ON TUESDAY THE STRONG SYSTEM OVER TX BETTER ORGANIZES & BEGINS LIFTING E-NE. SE-S FLOW AGAIN OVER THE CWA AS A WARM FRONT SETS UP WELL N OF THE CWA. SMALL CHANCE OF RAIN. TUESDAY NIGHT TO WEDNESDAY...COLD FRONT MAKES PROGRESS EAST TO MS VALLEY WITH SQUALL-LINE SET UP AHEAD OF IT. GOOD OMEGA LIFT SHOWING WITH IT INTO MS & AL. THIS PUSHES INTO THE CWA BY WEDNESDAY MORNING. COLD FRONT MOVES THROUGH THE CWA LATE WEDNESDAY TO THURSDAY MORNING. TIMING WILL BE KEY TO FORECAST. THANKSGIVING DAY SHOULD BE DRY WITH COOLER TEMPS WITH NW-N FLOW. DRY & COOL FOR FRIDAY. TEMPS WILL BE MILD UNTIL THE COLD FRONT PUSHES THROUGH. && .PRELIMINARY POINT TEMPS/POPS... TLH 74 58 77 60/ 50 10 20 10 PFN 74 64 76 65/ 80 20 20 20 DHN 70 60 75 62/ 80 20 30 30 ABY 70 58 75 60/ 60 20 30 30 VLD 75 59 78 59/ 40 10 20 20 CTY 78 59 80 60/ 20 10 10 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ CURRENT...WOOL/18 PREVIOUS...MCT fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1030 AM EST FRI NOV 19 2004 .UPDATE... MAIN CONCERN WITH CURRENT FORECAST PACKAGE IS WHEN SHOWERS WILL SPREAD NORTH ACROSS THE THUMB. VERY DRY AIR ABOVE THE SURFACE ACROSS NORTHERN LOWER MICHIGAN AND LAKE HURON WITH A 40C DEWPOINT DEPRESSION AT 850MB ON 12Z GAYLORD SOUNDING. LIGHT NORTH-NORTHEAST FLOW WITH DRY AIR ENTRAINMENT IS FIGHTING THE NORTHWARD PROGRESSION OF SHOWERS ACROSS THE THUMB AND SAGINAW BAY WITH CEILINGS STILL UP ABOVE 12000 FEET IN SOME AREAS. MODELS INDICATING GOOD ISENTROPIC LIFT SPREADING NORTH ACROSS THE THUMB ON 290K SURFACE BY 21Z BUT COND PRES DEFICITS STILL NOT SATURATED BY 00Z. WILL UPDATE WORDING TO BRING SHOWERS IN BY MID TO LATE AFTERNOON BUT WILL LEAVE CHANCE IN BEFORE THAT. WILL ALSO BUMP TEMPS DOWN A COUPLE DEGREES ACROSS THE AREA AS NOT MUCH RISE IS EXPECTED WITH DENSE CLOUD COVER. && KAHL .PREVIOUS DISCUSSION... 00Z RAOBS/WATER VAPOR LOOP SHOW UPPER TROUGH OVER THE CENTRAL PLAINS/MID-MISSISSIPPI VALLEY...WITH A SHORTWAVE RIDGE ACROSS THE WESTERN/SOUTHERN GREAT LAKES. OTHERWISE A NUMBER OF ADDITIONAL SHORTWAVES UPSTREAM...ACROSS THE NORTHERN/SOUTHERN HIGH PLAINS AND WEST COAST. SURFACE ANALYSIS SHOWS WEAK WAVE OVER EASTERN KANSAS/NEBRASKA...WITH A FRONT EXTENDING OUT THROUGH THE NORTHERN OHIO VALLEY. HIGH PRESSURE CONTINUES TO BUILD EASTWARD ACROSS THE NORTHERN GREAT LAKES/NORTHERN ONTARIO. REGIONAL RADARS SHOW WIDESPREAD PRECIP FROM LOWER MICHIGAN DOWN THROUGH SOUTHERN ILLINOIS/INDIANA. MAIN FORECAST ISSUE IS WITH PRECIP COVERAGE/DURATION TODAY/TONIGHT. ETA/GFS CONTINUE TO BE PRETTY SIMILAR INITIALLY WITH THE OVERALL TIMING OF THE MID MISSISSIPPI VALLEY LOW...LIFTING IT NORTHEAST THROUGH THE WESTERN GREAT LAKES...EVENTUALLY DEEPENING/MERGING WITH THE NORTHERN STREAM SYSTEM MOVING THROUGH SOUTHERN CANADA. ETA/GFS THEN DIVERGE BY THE END OF THE WEEKEND THOUGH...WITH RESPECT AS TO HOW THE NEXT SOUTHWESTERN LOW WILL DEVELOP. GFS IS MORE CUTOFF WITH THE LOW...WHILE THE ETA TRIES TO KEEP THE PATTERN MORE PHASED AND PROGRESSIVE. WILL LEAN TOWARD THE SLOWER GFS SOLUTION...WHICH IS THE PATTERN THAT SEEMS TO HAVE BEEN MORE FAVORED THIS FALL. 00Z CANADIAN GLOBAL ALSO SUPPORTS THIS SOLUTION. FOR TODAY...WILL RELY MORE ON AN EXTRAPOLATION OF CURRENT RADAR CONDITIONS AS MODELS STILL DO NOT HAVE A GOOD HANDLE ON THE EXTENT OF PRECIP COVERAGE. EVEN THE 06Z RUC DOES NOT BRING PRECIP INTO CENTRAL LOWER MICHIGAN UNTIL LATE MORNING...WHILE KLAN HAS REPORTED LIGHT RAIN SINCE 07Z. WE ARE SEEING STRONGER THETA-E ADVECTION WITH THIS INITIAL SURGE OF MOISTURE...WHICH IS WORKING TO QUICKLY OVERCOME THE 20C DEWPOINT DEPRESSIONS OBSERVED ON THE 00Z DTX SOUNDING. WHILE IT MAY NOT HAVE A GOOD HANDLE ON THE NORTHWARD EXTEND OF PRECIP INITIALLY...THE ETA DOES SEEM TO OFFER A REASONABLE SOLUTION WITH A SHARP CUTOFF TO PRECIP DUE TO DRY ADVECTION AROUND THE SURFACE HIGH BUILDING ACROSS NORTHERN ONTARIO. DETERMINING WHERE THIS NORTHERN EDGE SETS UP WILL BE TRICKY. BASED ON CURRENT RADAR TRENDS AND TIMING...WILL START OUT WITH CATEGORICAL POPS MORE AREAS EXCEPT FOR THE NORTHERN THUMB. SHORTWAVE RIDGE SHIFTS DOWNSTREAM TO THE LOWER GREAT LAKES BY THIS EVENING...WHICH SHOULD BE ENOUGH TO ALLOW PRECIP TO SPREAD A LITTLE FARTHER NORTH DURING THE AFTERNOON. 00Z MODELS DO NOT INDICATE MUCH FOCUSED LIFT THROUGH THE DAY BEHIND THE INITIAL SURGE OF WARM/MOIST ADVECTION EARLY THIS MORNING... HOWEVER WITH ABUNDANT MOISTURE AND PRECIP OBSERVED WELL BACK TO THE SOUTHWEST ALREADY...WILL STICK WITH CATEGORICAL POPS THROUGH THE DAY. AS FOR HIGHS TODAY...EXPECT A RATHER SMALL DIURNAL CLIMB GIVEN AMOUNT OF CLOUD COVER AND PRECIP ACROSS THE AREA. LITTLE CHANGE IN THE SOURCE AIRMASS COMPARED TO YESTERDAY /HIGHS IN THE LOW 60S/...HOWEVER A SOLID AND DEEP CLOUD DECK AND STRENGTHENING INVERSION DUE TO ELEVATED WARM ADVECTION WILL KEEP TEMPS IN CHECK. UPPER SHORTWAVE LIFTS TO WISCONSIN/LAKE MICHIGAN BY 12Z SATURDAY... LEADING TO SOME ADDITIONAL SURFACE CYCLOGENESIS...HELPING TO PROPEL THE SURFACE FRONT NORTHWARD THROUGH THE CWA AS A WARM FRONT. WITH ABUNDANT MOISTURE AND WEAK LIFT WILL CONTINUE WITH CATEGORICAL POPS TONIGHT ACROSS THE CWA. PRECIP MAY DIMINISH OVERNIGHT...ESPECIALLY ACROSS THE SOUTHERN CWA BEHIND THE FRONT. HOWEVER WILL HOLD ON TO CATEGORICAL POPS FOR LIGHT RAIN THROUGH THE NIGHT GIVEN PERSISTENT WEAK LIFT AHEAD OF THE SYSTEM. AS WAS THE CASE WITH TODAY...DO NOT EXPECT MUCH OF A DIURNAL TEMPERATURE SWING GIVEN AMOUNT OF LOW-LEVEL MOISTURE AND CLOUDS...IN ADDITION TO OUR PLACEMENT IN THE WARM SECTOR. WITH AMOUNT OF LOW-LEVEL MOISTURE /SURFACE CONDENSATION PRESSURE DEFICITS BELOW 10MB/...FOG MAY BE A CONCERN. GRADIENT REMAINS UP IN ADDITION TO CLOUDS AND PRECIP SO WILL JUST MENTION AREAS OF FOG IN THE PUBLIC FORECAST AT THIS POINT. HOWEVER IF PRECIP ENDS DURING THE NIGHT AND LOW-LEVEL MOISTURE FLUX CONTINUES...COULD SEE CLOUDS BUILD DOWN TO THE SURFACE FOR MORE OF A VISIBILITY PROBLEM. AT THIS POINT UPSTREAM...IFR CLOUDS AND VISIBILITY ONLY DOWN TO 1SM LOOK MOST COMMON. DEEPENING SURFACE WAVE MOVE THROUGH THE NORTHERN GREAT LAKES SATURDAY/SATURDAY NIGHT...FOLLOWED BY A SURFACE HIGH BUILDING DOWN INTO THE PLAINS/WESTERN GREAT LAKES. SOME MID-LEVEL DRY ADVECTION ON SATURDAY AND ESPECIALLY SATURDAY NIGHT...ALTHOUGH WEAK SYNOPTIC LIFT CONTINUES UNTIL THE NORTHERN STREAM TROUGH SHIFTS DOWNSTREAM SATURDAY NIGHT. WILL HOLD ONTO HIGH CHANCE POPS SATURDAY WITH LINGERING MOISTURE AND LIFT...AND LOW CHANCE POPS SATURDAY NIGHT UNTIL MOISTURE STARTS TO CLEAR AWAY. AS MENTIONED ABOVE...ETA/GFS DIVERGE HEADING INTO THE LATE WEEKEND. WITH THE PREFERRED GFS SOLUTION...UPPER LOW LINGERS LONGER ACROSS THE SOUTHWEST...AND DOES NOT PHRASE AS MUCH WITH THE NEXT NORTHERN STREAM WAVE. THIS ALLOWS A SURFACE HIGH TO BUILD INTO THE OHIO VALLEY BY F84/12Z MONDAY UNDER GENERALLY CONFLUENT UPPER FLOW. ETA IS NOTICEABLY DIFFERENT AT THE SURFACE WITH AN INVERTED TROUGH ACROSS GENERALLY BETWEEN THE MISSISSIPPI AND APPALACHIANS...DUE TO MORE SOUTHWESTERLY UPPER FLOW BETWEEN THE PHASED SYSTEMS. PREFER THE GFS...AND WILL KEEP A DRY FORECAST SUNDAY/MONDAY. SOUTHWESTERN LOW THEN EJECTS INTO THE SOUTHERN PLAINS ON TUESDAY...LEADING TO A BETTER MOISTURE RETURN AND OUR NEXT CHANCE FOR PRECIP. CURRENT GFS IS FASTER EJECTING THIS SYSTEM THAN THE 00Z RUN YESTERDAY...AND ALSO TAKES IT ON A MORE WESTERLY TRACK. CONSEQUENTLY THE CURRENT GFS IS MUCH WARMER THAN EARLIER RUNS. TWEAKED PRECIP TYPE ON TUESDAY A BIT...ALTHOUGH NOT TOO MUCH BEYOND THAT GIVEN UNCERTAINTY ASSOCIATED WITH THIS SYSTEM. && .DTX WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY...THIS AFTERNOON AND TONIGHT...OUTER SAGINAW BAY AND LAKE HURON NEARSHORE. && $$ BRAVENDER EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1021 AM EST FRI NOV 19 2004 .SHORT TERM... OVERALL FORECAST IN GOOD SHAPE AND NO CHANGES NEEDED TO THE TEXT PRODUCTS. MADE SOME MINOR ADJUSTMENTS IN THE GRIDS TO SKY CONDITIONS TO ACCOUNT FOR A BIT MORE SUNSHINE THIS MORNING. HOWEVER...STARTING TO SEE THE EFFECTS OF LOW LEVEL LAPSE RATES STEEPENING AND WITH SOME MOISTURE LINGERING IN THE LOWER ATMOSPHERE...STARTING TO SEE THE STRATOCUMULUS FORMING TO THE NORTH AND THIS WILL SPREAD SOUTHWARD AS TIME WEARS ON. THUS GOING FORECAST OF BECOMING PARTLY SUNNY MOST AREAS LOOKS REAL GOOD. TEMPERATURE AND WIND FORECASTS ON TRACK AS WELL...SO NO CHANGES TO THE GOING FORECAST AT THIS TIME. EVENSON && .PREV DISCUSSION FROM 251 AM... .SYNOPSIS... HI PRESS TO BUILD IN ACRS THE FA FROM THE NW TODAY AND TONITE. STORM SYS TO MOVE ACRS THE GREAT LKS REGION ON SAT AND SRN CANADA ON SAT NITE. CF TO MOVE ACRS THE FA ON SUN/SUN NITE. S/W TO MOVE ACRS THE FA ON SAT NITE. .SHORT TERM (THROUGH SUN NITE)... 00-03Z 13KM "DEVELOPMENT" RUC SHOWS TEMPS TO BE IN THE U30S-M40S TODAY WITH NORTHWESTERLY SFC WINDS AT 5-15 KTS. T1MAX TEMPS ARE IN THE L40S-M50S TODAY. RUC INDICATING THAT TEMPS MAY ACTUALLY TAKE A TUMBLE THROUGHOUT THE DAY TODAY. FEW TWEAKS TO FIRST PERIOD TEMPS/WINDS BASED ON THIS DATA AND CURRENT MESONET OBS. RUC SHOWS LOW-LVLS TO DRY OUT TODAY...BUT IT ALSO HANGS ONTO MOCLDY SKIES FOR TODAY ACRS THE FA. PW VALUES ACRS THE FA TO DROP TO BLO 0.5" TODAY. BUFCAN/88D MOSAIC SHOW SOME VERY LT RETURNS ACRS THE FA ATTM. IR SAT PIX SHOW THE LEADING EDGE OF THE CLEARING LINE JUST ENTERING THE ST LAW VLY ATTM. H85 CAA TO TAKE PLACE ACRS THE FA TODAY AND TONITE...THEN WAA TO DEVELOP ACRS THE FA FOR SAT AND SAT NITE...AND CAA TO REDEVELOP ON SUN/SUN NITE. H925 WET-BULB TEMPS TO GO NEGATIVE ACRS THE FA BY AROUND 00Z SAT...THEN POSITIVE BY AROUND 18Z SUN AND NEGATIVE AGAIN BY AROUND 12Z MON. MUCH OF THE LATEST THICKNESS AND ETA BUFR DATA SEEM TO SUPPORT ALL RAIN ACRS THE FA DURING THE SHORT-TERM PERIOD THOUGH (EXPECT MAYBE IN THE HIR TRRN ON SUN NITE?). LOW-LVL MSTR ADVECTION TO TAKE PLACE ACRS THE ON SAT AND SAT NITE. LOW-LVL MSTR TO INCREASE ACRS NY STATE LATE ON SAT AND AFFECT THE ENTIRE FA ON SAT NITE THROUGH MUCH OF SUN NITE. LOW-LVL LAPSE RATES TO BE HI ACRS THE FA ON SUN NITE. MID-LVL MSTR TO INCREASE ACRS THE FA LATE ON SAT AND INTO SAT NITE AND EARLY ON SUN. PW VALUES ACRS THE FA LOOK TO BE AROUND 0.5" ON SAT AND SUN NITE...AROUND 0.75" ON SAT NITE...AND 0.5-0.75" ON SUN. WILL CONT TO GO WITH SOME CLEARING ACRS MUCH OF THE FA TODAY AND WILL MOST LIKELY HANDLE ANY LINGERING PCPN/FG ACRS THE FA WITH THE STF. WOULD PREFER TO WAIT FOR THE COMPLETE PASSAGE OF THE UPR RIDGE ACRS THE FA BEFORE BRINGING ANY SIGNIFICANT PCPN INTO THE WRN FA LATE ON SAT...SO WILL HANG ONTO SCHC POPS FOR THERE FOR NOW. BEST CHC FOR ANY PCPN IN THE SHORT-TERM PERIOD LOOKS TO BE ON SAT NITE (WHERE LIKELY POPS WILL BE USED)...WITH LESSER CHCS AS SUN AND SUN NITE PROGRESS. LATER SHIFTS WILL NEED TO KEEP AN EYE ON THE P-TYPE ISSUE THOUGH. T1MIN TEMPS ARE MOSTLY IN THE 20S TONITE AND IN THE 30S ON SAT NITE. T1MAX TEMPS ARE MOSTLY IN THE 40S ON SAT. .LONG TERM (MON ONWARD)... NO CHANGES TO THE GOING FCST FOR NOW. PRELIM WRK ZONES AND ISC GRIDS AVAILABLE. ALL FINAL PRODUCTS BY AROUND 330 AM. MURRAY .AVIATION... AREAS OF MVFR CONDITIONS WITH LOCAL IFR WL PERSIST THRU ABOUT MID MORNING...THEN GRADUAL LIFTING OF CIGS WITH SCT CLDS/VFR CONDS DVLPG BY 18Z AS LOW LVL MSTR DECREASES. VFR TNGT WITH A FEW HI CLDS...OTRW SKC. N TO NW WINDS WL INCREASE TO 10-15 KTS BY MID MRNG... THEN BECOME LIGHT TNGT. KJC .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 315 PM CST FRI NOV 19 2004 .DISCUSSION... 18Z RUC AND 18Z ETA FAIRLY CLOSE WITH LAYERED MOISTURE...AND BEST QG CONV FIELDS. ALSO MATCHES CURRENT RADAR TRENDS AS TROUGH STARTS TO LIFT OUT. THIS POINTS TO RAIN ENDING FROM WEST TO DURING THE NIGHT..BUT WILL SPEED UP TIMING A BIT FROM CURRENT GRIDS OVER EAST CENTRAL MN. APPEARS THAT CHANCE OF SNOW NOW APPEARS MINIMAL AS LOW LAYER THICKNESS REMAINS ON "MILD" SIDE BUT 850 TEMPS ARE JUST ABOUT COLD ENOUGH. COLD ADVECTION WILL KEEP CLOUDS AROUND DURING THE MORNING MOST AREAS BUT INCREASING RIDGING AND LOW LEVEL ANTICYCLONIC CURVATURE SHOULD HELP CLEARING TREND IN THE WEST DURING THE AFTERNOON. HESITANT TO GET TOO AGRESSIVE WITH BLOWING OUT ALL THE CLOUDS WITH UPPER JET LURKING TO THE SOUTH. SHOULD BE SOME HIGH CLOUDS PUSHING INTO SOUTHERN AREAS LATER SATURDAY INTO SATURDAY AND PART OF SUNDAY. LOW LAYERS QUITE DRY THOUGH..SO SHOULD BE FAIR AMOUNT OF SUN IN NORTHERN AREAS ON SUNDAY. MAY EVEN END UP MOSTLY CLEAR. FWC AND MAV TEMPS GUIDANCE FAIRLY CLOSE AND GENERALLY LOOK OK. THESE VALUES ARE CLOSER TO NORMAL FOR THIS TIME OF YEAR WHERE AS ETA (MET)..ARE NEAR 10 DEGREES ABOVE NORMAL IN SOME CASES. WOULD THINK THAT TEMP REGIME FOLLOWING THIS SYSTEM SHOULD BE CLOSER TO NORMAL. LONGER TERM...MONDAY NIGHT THROUGH FRIDAY ON MON NIGHT CWA IN BETWEEN DEVELOPING LOW PRES OVER TX PANHANDLE AND LOW PRES OVER NW ONTARIO. BY TUE MORN...MODELS FCST TROF TO FORM THAT WILL CONNECT THE TWO SYSTEMS...PUTTING CWA IN AREA OF BROAD LIFT. WITH MAIN ENERGY BEING DRAWN INTO DEEPENING SRN STREAM LOW... LIFT OVER CWA ASSOC WITH INVERTED TROF WILL BE MAINLY LIGHT AND UNFOCUSED. HAVE OPTED TO ADD 30 POPS CWA WIDE TUE AND TUE NIGHT TO ACCOUNT FOR GENERAL AREAS OF PRECIP THIS TROF MAY PRODUCE...MAINLY IN THE FORM OF SNOW BUT A RAIN/SNOW MIX TO BEGIN WITH FAR S CWA. PRECIP SHUD COME TO AN END BY WED MORN WITH TROF RAPIDLY PUSHING INTO GREAT LAKES. NEXT CHANCE FOR PRECIP THU AFT/NIGHT WITH COLD FROPA. MILD AIR AHEAD OF FRONT DUE TO WARM 850MB JET MEANS PRECIP SHUD START OFF AS RAIN BEFORE CHANGING OVER TO A RAIN/SNOW MIX ALONG FRONT. DRY AGAIN FRI WITH STRONG HIGH NOSING IN FROM W. && MPX WATCHES/WARNINGS/ADVISORIES... .MN...NONE. .WI...NONE. && $$ RICHARDSON/MARGRAF mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 302 PM CST FRI NOV 19 2004 .DISCUSSION... PERSISTENT CLOUD COVER REMAINS ACROSS AREA...EVEN IN WAKE OF UPPER SYSTEM PASSAGE. UPPER SYSTEM COLD POOL PRODUCING ISOLATED SHRA ACROSS PORTIONS OF CFWA...BUT EXPECT THESE TO DISSIPATE AS MAX SENSIBLE HEAT PERIOD ABATES. ETA12 AND RUC INDICATE STRATUS WILL REMAIN ACROSS CFWA OVERNIGHT INTO MID-MORNING SATURDAY. DO NOT EXPECT REPEAT OF DENSE FOG OVERNIGHT...AS FOG IS NOT CLIMATOLOGICALLY FAVORED WITH WEST TO NORTHWEST SURFACE WIND FLOW. DID INTRODUCE SOME LIGHT FOG IN LATE NIGHT PERIOD...AS NEARLY SATURATED CONDITIONS AND LIGHT WINDS SHOULD ALLOW FORMATION. PREVIOUS FORECAST TEMPERATURES AND MINIMUMS OVERNIGHT LOOKED REASONABLE AND ONLY TWEAKED A LITTLE. AS MENTIONED EARLIER...EXPECT CLOUDS TO DISSIPATE BY MID-MORNING SATURDAY SO THEY WILL NOT IMPACT TEMPERATURES TOO MUCH. SLIGHT DOWNSLOPE COMPONENT OF BOUNDARY LAYER FLOW MAY HELP BOOST TEMPERATURES A LITTLE HIGHER THAN PREVIOUS FORECAST NUMBERS...SO MODIFIED A BIT. MAIN FORECAST CONCERN FOR NEXT WEEK CENTERS ON CUT OFF STORM SYSTEM MOVING OUT OF SOUTHWEST PART OF COUNTRY. TIMING IS ALWAYS A QUESTION MARK WITH THESE TYPES OF SYSTEMS AS IT IS NOT A KICKER IN THE SAME STREAM THAT WILL GET THE SHORT WAVE MOVING BUT RATHER A NORTHERN STREAM WAVE THAT SHOULD HAVE ENOUGH INFLUENCE TO GET IT MOVING. EUROPEAN AND 00Z GFS RUNS FAIRLY CLOSE ON TIMING UNTIL 00Z WEDNESDAY WHEN EUROPEAN MODEL RAPIDLY WEAKENS AND ACCELERATES THIS WAVE. THE UKMET IS THE OUTLIER WITH ONLY BREAKING OFF PART AND LEAVING A SUBSTANTIAL PART OF THE SHORT WAVE BEHIND. 12Z ETA SHOWING AN EVEN FASTER SOLUTION THAN THE GFS. WITH IT BEING A CLOSED OFF SYSTEM HAVE DOUBTS ABOUT THE WAVE MOVING OUT AS FAST AS ETA DEPICTS SO WILL LEAN TOWARD GFS SOLUTION...WHICH WOULD MEAN MAINLY A TUESDAY EVENT. SOME CONCERN TUESDAY NIGHT WITH SYSTEM MOVING PAST WITH ENOUGH COLD AIR DROPPING INTO BACKSIDE OF THIS SYSTEM...THAT RAIN MAY CHANGE OVER TO SOME SNOW IN A DEFORMATION BAND TO THE NORTHWEST OF THE SHORT WAVE. WILL MENTION SNOW FOR THE OVERNIGHT HOURS...BUT AT THIS POINT...WITH SO MANY TIMING QUESTIONS NOT GOING FOR ACCUMULATING SNOW. SHOULD NOT BE CATCHING MUCH OF A BREAK FROM THE CLOUDY SITUATION AS ONCE THE LOW LEVEL MOISTURE FINAL CLEARS...WE SHOULD BEGIN TO SEE MID LEVEL MOISTURE MOVING IN AS A SOUTHWEST FLOW SETS UP WITH SHORT WAVE DIGGING INTO THE SOUTHWESTERN PART OF COUNTRY. THUS NOT EXPECTING TO SEE A LOT OF SUNSHINE. SURFACE HIGH DROPPING IN ON SUNDAY WILL ALSO BRING SLIGHTLY COOLER WEATHER FOR THE FIRST PART OF THE WEEK...AND WITH STORM SYSTEM MOVING THROUGH ON TUESDAY PULLING IN MORE CHILLY WEATHER FOR WEDNESDAY AND THURSDAY...NOT EXPECTING TO SEE ANY ABOVE NORMAL DAYTIME HIGHS THROUGH THANKSGIVING. SF/PC .AVIATION IFR CONDITIONS WILL CONTINUE TO DIMINISH AS DRIER AIR INFILTRATES AREA THIS AFTERNOON AND EVENING. STRATUS WILL HOLD TOUGH OVERNIGHT...AND DO NOT EXPECT CEILINGS TO LIFT ABOVE MVFR THRESHOLD. COOLING TEMPERATURES OVERNIGHT AND LIGHT WINDS WILL AID IN PATCHY FOG FORMATION IN THE 07-12Z TIME PERIOD...BUT DENSE FOG...THAT IS VISIBILITIES BELOW 1 STATUTE MILE...ARE NOT EXPECTED... WITH PREVAILING VISIBILITIES OF 4 TO 6 MILES MORE LIKELY. SF && .AVIATION... 1034 AM... AREAS OF LOCALLY DENSE FOG LINGER AROUND THE KC METRO AREA THIS MORNING. FOG TIED TO A MESO-B WARM FRONT THAT STRETCHES ACROSS THE AREA. WILL KEEP VISIBILITIES IN THE ONE-QUARTER TO ONE-HALF MILE RANGE THROUGH 18Z...THEN WILL GRADUALLY INCREASE AS SURFACE COLD FRONT MOVES ACROSS AREA. BASED ON RUC/ETA CONDENSATION PRESSURE DEFICIT PROGS...IFR CONDITIONS WILL LINGER UNTIL 21-22Z...WITH MVFR CONDITIONS HOLDING ON THROUGH 20/09-12Z. SF && .PREV DISCUSSION... 226 AM... EARLY MORNING WATER VAPOR IMAGERY AND THE PROFILER NETWORK ILLUSTRATE AN UPPER LOW TRAVELING ACROSS THE MISSOURI BOOTHEEL REGION...AND A SECONDARY SHORTWAVE LIFTING NORTH INTO IOWA. MEANWHILE...SURFACE OBS DEPICT A LOW PRESSURE CENTER ACROSS SOUTHEAST NEBRASKA...WITH AN ATTENDANT COLD FRONT STRETCHING SOUTH ACROSS EASTERN KANSAS/OKLAHOMA...AND A WARM FRONT LYING PARALLEL TO THE IOWA MISSOURI BORDER. THE MAJORITY OF THE PRECIPITATION ASSOCIATED WITH THE TRAILING SHORTWAVE HAS SHIFTED TO THE NORTH OF THE FORECAST AREA...ALTHOUGH WIDELY SCATTERED ECHOES ARE STILL APPEARING OVER NORTHERN MISSOURI ON RADAR IMAGERY. HIGHEST POPS WILL REMAIN CONFINED TO THE NORTHERN EDGE OF THE FORECAST AREA IN THE VICINITY OF THE WARM FRONT THIS MORNING. WILL MAINTAIN CHANCE POPS ACROSS THE NORTHERN THREE FOURTHS OF THE FORECAST AREA THROUGH THE AFTERNOON WITH THE COLD FRONTAL PASSAGE. TEMPERATURES WILL NOT RISE MUCH TODAY DUE TO THE STRATUS DECK AND FRONTAL INFLUENCE. HAVE ELIMINATED SLIGHT CHANCE POPS FROM SATURDAY...AS THIS APPEARS TO BE A TIMEFRAME BETWEEN SHORTWAVES. HOWEVER...WILL MAINTAIN SLIGHT CHANCE POPS ACROSS MOST OF THE CWA FOR SATURDAY NIGHT AND SUNDAY...AS THE GFS PROGS A WEAK IMPULSE AND ISENTROPIC LIFT OVER EASTERN KANSAS AND WESTERN MISSOURI. THE ECMWF AND LATEST GFS SOLUTIONS BOTH FORECAST THE HEALTHY SOUTHWEST TROUGH TO EJECT EAST ACROSS THE CENTRAL CONUS AT THE BEGINNING OF THE UPCOMING WORK WEEK. DUE TO IMPROVING MODEL CONSENSUS...HAVE INTRODUCED CHANCE POPS MONDAY NIGHT THROUGH TUESDAY NIGHT. LS && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. $$ WFO EAX mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 1034 AM CST FRI NOV 19 2004 .DISCUSSION... .AVIATION AREAS OF LOCALLY DENSE FOG LINGER AROUND THE KC METRO AREA THIS MORNING. FOG TIED TO A MESO-B WARM FRONT THAT STRETCHES ACROSS THE AREA. WILL KEEP VISIBILITIES IN THE ONE-QUARTER TO ONE-HALF MILE RANGE THROUGH 18Z...THEN WILL GRADUALLY INCREASE AS SURFACE COLD FRONT MOVES ACROSS AREA. BASED ON RUC/ETA CONDENSATION PRESSURE DEFICIT PROGS...IFR CONDITIONS WILL LINGER UNTIL 21-22Z...WITH MVFR CONDITIONS HOLDING ON THROUGH 20/09-12Z. SF && .PREV DISCUSSION... 226 AM... EARLY MORNING WATER VAPOR IMAGERY AND THE PROFILER NETWORK ILLUSTRATE AN UPPER LOW TRAVELING ACROSS THE MISSOURI BOOTHEEL REGION...AND A SECONDARY SHORTWAVE LIFTING NORTH INTO IOWA. MEANWHILE...SURFACE OBS DEPICT A LOW PRESSURE CENTER ACROSS SOUTHEAST NEBRASKA...WITH AN ATTENDANT COLD FRONT STRETCHING SOUTH ACROSS EASTERN KANSAS/OKLAHOMA...AND A WARM FRONT LYING PARALLEL TO THE IOWA MISSOURI BORDER. THE MAJORITY OF THE PRECIPITATION ASSOCIATED WITH THE TRAILING SHORTWAVE HAS SHIFTED TO THE NORTH OF THE FORECAST AREA...ALTHOUGH WIDELY SCATTERED ECHOES ARE STILL APPEARING OVER NORTHERN MISSOURI ON RADAR IMAGERY. HIGHEST POPS WILL REMAIN CONFINED TO THE NORTHERN EDGE OF THE FORECAST AREA IN THE VICINITY OF THE WARM FRONT THIS MORNING. WILL MAINTAIN CHANCE POPS ACROSS THE NORTHERN THREE FOURTHS OF THE FORECAST AREA THROUGH THE AFTERNOON WITH THE COLD FRONTAL PASSAGE. TEMPERATURES WILL NOT RISE MUCH TODAY DUE TO THE STRATUS DECK AND FRONTAL INFLUENCE. HAVE ELIMINATED SLIGHT CHANCE POPS FROM SATURDAY...AS THIS APPEARS TO BE A TIMEFRAME BETWEEN SHORTWAVES. HOWEVER...WILL MAINTAIN SLIGHT CHANCE POPS ACROSS MOST OF THE CWA FOR SATURDAY NIGHT AND SUNDAY...AS THE GFS PROGS A WEAK IMPULSE AND ISENTROPIC LIFT OVER EASTERN KANSAS AND WESTERN MISSOURI. THE ECMWF AND LATEST GFS SOLUTIONS BOTH FORECAST THE HEALTHY SOUTHWEST TROUGH TO EJECT EAST ACROSS THE CENTRAL CONUS AT THE BEGINNING OF THE UPCOMING WORK WEEK. DUE TO IMPROVING MODEL CONSENSUS...HAVE INTRODUCED CHANCE POPS MONDAY NIGHT THROUGH TUESDAY NIGHT. LS 855 PM THU... EVENING OBJECTIVE UPPER AIR ANALYSIS AND WATER VAPOR IMAGERY INDICATE REMNANT UPPER LOW OVER OZARKS CONTINUING TO SLOWLY TRANSLATE EASTWARD WITH DEFORMATION AXIS EXTENDING ACROSS NORTHERN MO...WHILE FURTHER WEST SECONDARY SHORTWAVE NOTED ACROSS HIGH PLAINS OF WESTERN NE/KS. SURFACE LOW LOCATED ACROSS EAST CENTRAL KS NEAR KMHK AS OF 02Z...WITH WARM FRONT EXTENDING ACROSS EXTREME NORTHWEST MO. LARGE SCALE LIFT AND ASSOCIATED PRECIPITATION RESULTING FROM OZARKS SHORTWAVE HAS SHIFTED NORTH AND EAST OF FORECAST AREA...AS NOTED IN REGIONAL RADAR IMAGERY...AND AS A RESULT HAVE LOWERED POPS INTO LOW CHANCE CATEGORY ACROSS ALL BUT FAR NORTHERN MO FOR REMAINDER OF NIGHT. DRIER AIR ALOFT LIKELY ASSOCIATED WITH SUBSIDENCE BEHIND OZARKS SHORTWAVE HAS ALSO RESULTED IN CEILINGS LIFTING CONSIDERABLY ACROSS MUCH OF FORECAST AREA THIS EVENING. HOWEVER EXPECT THIS TO BE TEMPORARY...AS LOW CLOUDS ARE NOTED ACROSS MUCH OF EASTERN KS AS WELL AS SOUTHERN MO. EXPECT AREAS OF DRIZZLE AND POSSIBLY FOG TO ACCOMPANY LOWER CEILINGS LATER TONIGHT GIVEN HIGH MOISTURE CONTENT OF AIRMASS IN PLACE ACROSS THE AREA. HAVE ADJUSTED TEMPERATURE TRENDS BASED ON CURRENT OBSERVATIONS...BUT EXPECT LITTLE IF ANY ADDITIONAL COOLING THROUGH OVERNIGHT HOURS. SEAMAN && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. $$ WFO EAX mo AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE STATE COLLEGE PA 1108 AM EST FRI NOV 19 2004 .SHORT TERM (THIS AFTERNOON AND TONIGHT)... UPDATED SELECTED GRIDS FOR THIS AFTERNOON AND TONIGHT...MAINLY TO BETTER SPECIFY THE ONSET OF RAIN (BUT ALSO TO TRIM TEMPS A FEW DEG ACROSS THE SOUTH AND MIDDLE/LOWER SUSQ VALLEY). A SHIELD OF STEADY...AND AT TIMES MODERATE RAIN WAS MOVING SLOWLY NE ACROSS THE LAUREL HIGHLANDS LATE THIS MORNING. ETA POORLY HANDLING THE SOUTHERN EXTENT OF THIS INITIAL BATCH OF RAIN WITH THE GFS AND RUC DOING A MUCH BETTER JOB. LOW LEVEL DRIER AIR ADVECTING SOUTH INTO OUR CENTRAL AND EASTERN ZONES AND AN UPPER SHORT WAVE RIDGE HOLDING TOUGH ACROSS THESE SAME AREAS THIS AFTERNOON AND EARLY EVENING WILL SLOWLY IMPROVE/BREAK UP THE LOWER...STRATO CU DECK...AND KEEP CONDITIONS DRY AND MILD THROUGH EARLY EVENING. A SHIELD OF MID CLOUDS WILL CONTINUE TO ADVANCE SLOWLY NE AND THICKEN UP THROUGH THIS EVENING...ALLOWING JUST TIMES OF DIM SUNSHINE TO OCCUR ACROSS THE SUSQ VALLEY REGION. && .PREVIOUS DISCUSSION... THE FOLLOWING WAS ORIGINALLY ISSUED AT 410 AM EST FRI NOV 19 2004 SHORT TERM (TODAY AND SATURDAY)... LATEST RUNS HAVE BACKED WAY OFF ON THE TIMING OF THE INCOMING RAIN. WITH OLD RULE OF THUMB SHOWING 700 RIDGE PASSING NOT UNTIL AFTER ABOUT MID DAY...I DELAYED THE ONSET OVER ALL OF MY ZONES...AND STILL WONDER IF I AM SLOW ENOUGH. I DID KEEP MY FAR EAST DRY THRU LATE DAY IN ACCORDANCE WITH THE HIGH RES ETA...BUT DID EVENTUALLY WET THINGS UP OVERNIGHT. ENSEMBLE POPS ARE 80+ OVERNIGHT SO I JUST WENT FOR 100 OVER MOST OF MY CWA. WARM ADVECTION AND SHOWERS CONTINUE INTO SAT. RETREATING JET ENTRANCE OVER NEW ENG IS FCST TO SUPPORT A SFC HIGH IN ERN CANADA AND A COLD AIR DAMMING SCENARIO. LI PROGS ON BOTH ETA AND GFS SHOW COOL AIR HOLDING TOUGH MOST OF SATURDAY SUGGESTING A CHILLY DAMP DAY. ENSEMBLE MOS SHOWS A HIGH WITHIN A COUPLE OF DEGREES OF 50 MOST AREAS...BUT THINK MUCH OF THE DAY WILL BE SPENT STRUGGLING THRU THE 40S WITH OCNL SHOWERS. NOT A GREAT DAY FOR OUTDOOR SPORTING OR OTHER RECREATIONAL ACTIVITIES. LA CORTE LONG TERM (SUNDAY THROUGH THURSDAY)... MUCH DISAGREEMENT ARISES BETWEEN ETA AND GFS FOR LATER SUN AND MONDAY. IN FACT 84HR PROG FOR 12Z MON COULD HARDLY LOOK MORE DIFFERENT. GFS HAS A RESPECTABLE SFC HIGH BUILDING IN FROM THE MIDWEST. IN THE EXACT SAME PLACE THE ETA SHOWS A SLOW MOVING WAVY SFC FRONT WITH PRESSURES ABOUT 10-15MB LOWER THAN THE GFS. DIFFERENCES SEEM CENTERED ON THE ETA BEING MUCH FASTER EJECTING AN UPPER LOW FROM THE SERN US RESULTING IN THE DEVELOPMENT OF A POS TILT TROF INTO THE WRN GR LAKES. THE GFS...BEING SLOWER...HAS A FLAT RIDGE THRU THE CTRL US. EVENTUALLY ONE OF THE MODELS WILL PROVE MOST CORRECT AND THE EXPECTED STORM SYSTEM...CURRENTLY SEEN IN THE WATER VAPOR DIVING SOUTH THRU NRN CALIFORNIA...WILL EJECT AND BRING UNSETTLED CONDITIONS BACK TO THE REGION. NEW MREF STARTING TO SHOW THE SLOWER IDEA SUGGESTING THAT PRECIP WILL BE MORE LIKE MID WEEK VERSUS EARLY WEEK. LA CORTE AVIATION... WIDE RANGE IN CONDITIONS THIS AM. IPT DOWN TO 100 AND 1/4 AT TIMES...BUT MOST SITES RUNNING ABOUT 4SM AND 2500 TO 4000. FRONT AND DRY AIR WELL TO THE NORTH OF LAKE ONTARIO. SOME IMPROVEMENT BY LATE MORNING...EARLY AFTERNOON...GIVING WEAK RIDGING...BUT MVFR/IFR CONDITIONS WILL PREVAIL FOR MUCH OF TODAY INTO TONIGHT. MARTIN && .CTP WATCHES/WARNINGS/ADVISORIES... PA...NONE. && $$ SHORT TERM (UPDATE)...LAMBERT pa