AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1045 AM CST WED NOV 22 2006 .DISCUSSION... FORECAST LOOKS ON TRACK TODAY AND ONLY MINOR UPDATE TO THE HOURLY GRIDS TODAY. PLENTIFUL SUNSHINE TODAY WITH JUST SOME THIN CIRRUS CLOUDS STREAKING ACROSS CENTRAL IL. HIGHS IN THE MID TO UPPER 50S WITH SSE WINDS 5 TO 15 MPH. 16Z/10 AM SURFACE MAP SHOWS 1035 MB HIGH PRESSURE OVER NEW ENGLAND AND RIDGING SW ACROSS THE LOWER OHIO VALLEY IN FAR SE IL AND ACROSS THE LOWER MS VALLEY. 1004 MB LOW PRESSURE WAS OVER CENTRAL LAKE WINNIPEG WITH A WEAK TROF OF LOW PRESSURE EXTENDING SOUTH ACROSS THE HIGH PLAINS. NEARLY SUNNY SKIES ACROSS CENTRAL/SE IL THIS MORNING WITH JUST SOME THIN CIRRUS FROM THE IL RIVER VALLEY NW AND HAS BEEN DISSIPATING AS IT DRIFTS EAST. TEMPS WERE IN THE LOWER 40S EASTERN IL AND UPPER 40S WESTERN IL WITH QUINCY UP TO 51F. LOW DEWPOINTS IN THE LOWER 30S WITH SSE WINDS 5 TO 15 MPH. ALOFT A 589 DM 500 MB HIGH PRESSURE WAS OVER NORTHERN MEXICO/TX RIO AND RIDGING INTO IL WHILE 553 DM CUTOFF 500 MB LOW WAS EAST OF MRYTLE BEACH SC. RUC AND NAM/WRF KEEP UPPER LEVEL RIDGE OVER IL AND SURFACE HIGH JUST EAST SO AMPLE SUNSHINE AND SSE WINDS TO CONTINUE. YESTERDAY WE ONLY MIXED UP TO 950 MB WHICH SHOULD BE ABOUT THE SAME TODAY TO GIVE HIGHS IN THE MID TO UPPER 50S. && .PREV DISCUSSION... WITH STRONG RIDGING OVER THE ATLANTIC... AND A CUTOFF LOW OFF THE COASTAL CAROLINAS... THE MEAN UPPER LEVEL PATTERN FARTHER UPSTREAM ACROSS THE CONUS WILL REMAIN STATIC OVER THE NEXT FEW DAYS. TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGH AT LEAST THE WEEKEND. A WEAK COLD FRONT WILL APPROACH FRIDAY WITH LITTLE FANFARE... BUT THIS STALLED OUT BOUNDARY WILL BECOME THE FOCUS FOR A MORE DISTURBED WEATHER PATTERN NEXT WEEK. SHORT TERM...TODAY THROUGH SATURDAY... TEMPERATURES YESTERDAY STAYED IN THE LOWER TO MIDDLE 50S ACROSS MOST OF THE AREA AS THE STRONGEST WAA REMAINED OFF TO OUR WEST... AND MIXING WAS RATHER LIMITED WITH A STRONG INVERSION OVERHEAD. OVERALL THE WX MAP TODAY WILL LOOK VERY MUCH LIKE A CARBON COPY OF YESTERDAY. WAA WILL REMAIN FOCUSED OVER IOWA AS THE H85 RIDGE AXIS WILL REMAIN ALONG THE MISSISSIPPI RIVER VALLEY. CONTINUED STRONG INVERSION WILL KEEP MIXING POTENTIAL LIMITED. OVERALL... EXPECT TODAY TO BE SLIGHTLY WARMER THAN YESTERDAY... BUT REMAIN IN THE MIDDLE TO UPPER 50S... WARMEST AROUND SPI AND IJX. NIGHT TIME TEMPS WILL BE ON THE UPSWING OVER THE NEXT COUPLE DAYS... BUT WITH SFC RIDGE AXIS OVER THE SOUTHEASTERN PORTION OF THE CWA TONIGHT... WE COULD STILL DIP DOWN INTO THE UPPER 20S. FARTHER WEST... WARMER AIR WILL BE FILTERING IN... ALONG WITH A CONTINUED STREAM OF CIRRUS CLOUDS WHICH WILL ALLOW TEMPS TO REMAIN IN THE 30S. FOCUS OF WAA WILL SHIFT ACROSS OUR REGION THURSDAY... BRINGING UPPER 50S AND POSSIBLY AROUND 60 SOUTH OF I-72. COLD FRONT FOR FRIDAY NIGHT CONTINUES TO LOOK SLOW AND WEAK. LACK OF CLOUD COVER... AND INCREASED SFC GRADIENT SHOULD ALLOW A LITTLE MORE MIXING THAN THE PAST COUPLE DAYS... AND THIS MAY BE THE WARMEST DAY ACROSS FAR EAST CENTRAL ILLINOIS. GFS TRIES TO PRODUCE SOME QPF ALONG THE STALLED OUT COLD FRONT ON SATURDAY... BUT WILL CONTINUE TO DOWNPLAY THIS POTENTIAL AS AIR MASS WILL REMAIN DRY... WITH BEST RETURN FLOW NOT COMING IN UNTIL EARLY NEXT WEEK. LONG TERM...SUNDAY THROUGH TUESDAY... BY THE WEEKEND... THE CUTOFF LOW OFF THE EAST COAST WILL HAVE LIFTED OUT... ALLOWING THE ATMOSPHERIC LOG JAM TO FREE UP ACROSS THE CONUS AND NORTH PACIFIC. LOOKS LIKE A DECENT PATTERN SHIFT ON TAP FOR EARLY NEXT WEEK. FRIDAYS FRONT WILL STALL OUT ACROSS OUR AREA... BUT THE LOW LEVEL BAROCLINIC ZONE WILL REMAIN JUST TO OUR NORTH. UPPER LEVEL RIDGING WILL BUILD ALONG THE GULF AND EAST COASTS... WITH A DEEPENING TROUGH ACROSS THE WEST. THIS WILL RESULT IN FAIRLY STRONG SOUTHWESTERLY FLOW ALOFT... WITH THE SUBTROPICAL JET NOSING INTO THE AREA AND RESULTING IN A DUAL JET STRUCTURE OVER THE MIDWEST. SOUTHWEST FLOW WILL KEEP TEMPS ABOVE NORMAL THROUGH MOST OF THE PERIOD. FREQUENT SHORT WAVE DISTURBANCES EJECTING FROM THE DEEPENING TROUGH WILL PASS THROUGH THE REGION SUN-TUE... INTERACTING WITH THE STALLED OUT BAROCLINIC ZONE... AND BRINGING THE CHANCE FOR PRECIP TO THE AREA THROUGH THE PERIOD. DIFFICULT TO PINPOINT THE DETAILS THIS FAR OUT WITH RELATIVELY SMALL UPPER DISTURBANCES MOVING THROUGH. WHAT WILL BE MOST IMPORTANT AS WE HEAD INTO NEXT WEEK IS WHAT WILL HAPPEN AS THIS WESTERN TROUGH FINALLY SHIFTS EAST AND SWINGS THROUGH THE AREA. A MORE SIGNIFICANT SYSTEM WITH GREATER PRECIP POTENTIAL LOOKS LIKELY BY MIDWEEK. GFS AND ECMWF DIFFER WITH THE TIMING... ECMWF HAS BEEN SLOWER... AND THIS SEEMS MOST LIKELY WITH STRONG RIDGING ALONG THE EAST COAST. GFS HAS BEEN TRENDING IN THIS DIRECTION OVER THE PAST 24 HRS AS WELL. SUCH A SOLUTION WOULD BRING HIGHEST PRECIP CHANCES ON WEDNESDAY... SO THE TUE POPS REMAIN SLIGHTLY DOWNPLAYED CONSIDERING THE HIGHER POTENTIAL JUST OUTSIDE THE FORECAST PERIOD. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ HUETTL/HARDIMAN il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 945 AM MST WED NOV 22 2006 .UPDATE...HAVE MADE SOME MINOR ADJUSTMENTS IN THE FIRST PERIOD. SURFACE TROUGH HAS PUSHED THROUGH MOST OF THE AREA WITH NORTH TO NORTHWEST WINDS A BIT STRONGER (10-15 MPH) THEN PREVIOUSLY EXPECTED. 850 TEMPERATURES VERY SIMILAR TO YESTERDAY WITH HIGHS GENERALLY IN THE 70-74 RANGE. HAVE TWEAKED A FEW AREAS UP A DEGREE OR TWO AS A RESULT. A FEW RECORDS IN JEOPARDY BUT NOT EXPECTED TO BE REACHED INCLUDE YUMA COLORADO...COLBY KANSAS...AND MCCOOK NEBRASKA. WAVE ENHANCED CIRRUS STARTING TO DISSIPATE EXCEPT ACROSS THE FAR NORTHWEST WHERE ITS EXPECTED TO CONTINUE. OTHER ADJUSTMENTS WERE TO THE HOURLY DEWPOINT GRIDS WHICH GENERALLY FOLLOW THE 12Z NAM/15Z RUC FORECASTS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ DDT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CARIBOU ME 1000 AM EST WED NOV 22 2006 .SYNOPSIS...HIGH PRESSURE WILL BUILD ACROSS NORTHERN MAINE THROUGH TONIGHT THEN MOVE TO THE EAST THURSDAY. LOW PRESSURE WILL LIFT NORTH ALONG THE COAST THURSDAY NIGHT...THEN TRACK EAST OF THE GULF OF MAINE FRIDAY. THIS LOW COULD BRING A CHANCE OF RAIN TO DOWNEAST AREAS THURSDAY NIGHT AND FRIDAY. && .SHORT TERM /REST OF TODAY/... EXPANSIVE AREA OF CIRRUS CLOUDS STREAMING AHEAD OF MID ATLANTIC LOW HAS MOVED ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. HAVE UPDATED SKY FORECAST FOR MUCH OF THE SOUTHERN CWA. HIGH PRESSURE OVER NORTHERN MOST SECTIONS IS ERODING SOME OF THE CIRRUS ALONG THE NORTHERN PERIPHERY. EXPECT THIS TREND TO CONTINUE...THUS SOME BREAKS OF SUN COULD RETURN TO THE DOWNEAST INTERIOR LATER THIS AFTERNOON. HAVE ALSO MADE SLIGHT ADJUSTMENTS TO FIRST PERIOD WINDS BASED ON LATEST RUC. WILL LOOK AT 12Z GUIDANCE BEFORE MAKING ANY ADDITIONAL CHANGES. && .PREV DISCUSSION... SYNOPSIS...HIGH PRESSURE WILL BUILD ACROSS THE REGION THROUGH TONIGHT THEN MOVE TO THE EAST THURSDAY. LOW PRESSURE WILL LIFT NORTH ALONG THE COAST THURSDAY NIGHT...THEN TRACK EAST OF THE GULF OF MAINE FRIDAY. THIS LOW COULD BRING A CHANCE OF RAIN TO DOWNEAST AREAS THURSDAY NIGHT AND FRIDAY. SHORT TERM /TODAY THROUGH THURSDAY/... MAIN MAP FEATURES INCLUDE A STRONG AREA OF LOW PRESSURE THAT IS EXPECTED TO MOVE TO THE EAST BY THE END OF THIS PERIOD. TO THE SOUTH OF NEW ENGLAND AN INTENSE LOW PRESSURE SYSTEM IS DEVELOPING OFF THE CAROLINA COAST. THE GFS TRACKS THIS LOW OUT TO SEA WELL SOUTH OF NEW ENGLAND THURSDAY INTO FRIDAY. THE NAM ON THE OTHER HAND BRINGS THE LOW ACROSS THE OTHER PORTION OF THE GULF OF MAINE FRIDAY MORNING. HAVE CHOSEN TO BASE THE FORECAST ON THE GFS SINCE IT HAS BEEN VERY CONSISTENT OVER THE LAST SEVERAL RUNS WITH THE TRACK OF THIS LOW WHILE THE LATEST NAM RUN IS A MORE RADICAL DEPARTURE. HAVE CREATED TEMPERATURE AND WIND GRIDS WITH A COMBINATION OF THE MAV/MET. HAVE LOWER MIN TEMPERATURES TONIGHT BELOW MOS GUIDANCE DUE TO EXPECTED RADIATIONAL COOLING. THE SKY GRIDS HAVE BEEN MANUALLY MODIFIED TO HANDLE AREA OF MID CLOUDS MOVING ACROSS THE NORTH THIS MORNING AND TO KEEP HIGH CLOUD PERCENTAGES TO OVER SOUTHERN AREAS THURSDAY. POPS FOR THIS PERIOD HAVE BEEN KEPT MOSTLY BELOW 10 PERCENT DUE TO THE SOUTHERN TRACK OF THE LOW. THERE ARE MINIMAL POPS OVER THE SOUTH THURSDAY NIGHT AS THE LOW PASS SOUTH OF THE FORECAST AREA. LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... LATEST MODEL CONSENSUS IN REASONABLE AGREEMENT IN THE LONG TERM W/ COASTAL SYSTEM INITIALLY LIFTING N TOWARD THE FA BEFORE PULLING E OF THE AREA ON FRI... GFS/NAM-WRF BOTH BRING NRN EDGE OF THE PRECIP SHIELD INTO OUR DOWNEAST AREAS BY THU EVE W/ THE NAM-WRF JUST A BIT MORE AGGRESSIVE. USING A COMPROMISE APPROACH YIELDS MAINLY CHC POPS THU NGT INTO FRI AM DOWNEAST W/ POPS PULLING EWRD OUT OF THE AREA BY FRI AFTN. THIS IS FASTER THAN PREVIOUS SOLNS HAD SHOWED AND HAVE ADJUSTED THE GRIDS ACCORDINGLY. LATER SHIFTS MAY NEED TO BOOST POPS UP TO LIKELY IF PRECIP SHIELD SHIFTS JUST A BIT FURTHER N BUT BELIEVE CHC POPS WARRANTED ATTM. FOR THE WEEKEND...ALL MODELS SHOW THIS SYSTEM WELL E OF THE AREA W/ XTNSV HGH PRES RDG CENTERED OVER THE AREA THRU SAT... SEE NO REASON TO CONT TO CARRY CHC POPS DOWNEAST SO HAVE ADJUSTED SKY COVER AND DROPPED POPS FOR THE DOWNEAST REGION. GFS HINTS AT A WEAK SYSTEM GRAZING FAR NRN AND NWRN AREAS SAT NGT INTO SUN AND HAVE INCREASED CLDS THERE BUT WILL HOLD OFF ON ANY POPS ATTM... APPEARS THAT THE MILD WX PTRN OF LATE WILL PERSIST THRU THE WEEKEND W/ ABOVE AVG TEMPS CONTG... AVIATION... VFR CONDS ANTICIPATED AT ALL TAF SITES THRU THE NXT 24 HRS... MARINE... FOR TODAY HAVE USED THE NAM12 WINDS WHICH ARE PREFERRED IN THE LIGHT WIND ENVIRONMENT UNDER THE HIGH. FOR TONIGHT THRU THURSDAY HAVE TRANSITIONED TO THE GFS WIND FIELD SINCE THE GFS TRACK OF LOW PRESSURE PASSING TO THE SOUTH OF NEW ENGLAND IS PREFERRED. FOR SEAS HAVE INITIALIZED THE WAVE GRIDS WITH THE WNA WAVE WATCH III. CURRENT OBSERVATIONS SHOWING SEAS STILL AROUND 1 FOOT. EXPECT SEAS TO BUILD TONIGHT AS NORTHEAST WIND INCREASES AND SWELL FROM SOUTHERLY SYSTEM ENTERS THE COASTAL WATERS. THE GFS HAS BEEN TRENDING TOWARDS A MORE NORTHEAST/SOUTHWEST DIRECTION FOR THE FETCH AROUND THE OCEAN LOW AS OPPOSED TO THE MORE EASTERLY ORIENTATION OF YESTERDAYS RUNS. THIS WILL DIRECT THE LARGEST SWELL FIELD SOUTH OF OUR COASTAL WATERS...THE WAVE MODEL SEEMS TO DO A REASONABLE JOB HANDLING THIS SO HAVE NOT MADE ANY MANUAL CHANGES. HAVE HIGHLIGHTED THE MENTION OF SWELL IN THE FORECAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ SHORT TERM/MARINE...LULOFS me AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1013 PM EST WED NOV 22 2006 .UPDATE...BESIDES SOME HIGH LEVEL PACIFIC MOISTURE OVERSPREADING THE AREA IN THE FORM OF SOME SCATTERED CIRRUS...NOT A WHOLE LOT GOING ON IN THE WEATHER DEPARTMENT THIS EVENING. LATEST SURFACE/SATELLITE/RUC ANALYSIS SHOWS SURFACE HIGH PRESSURE RIDGE NOSING SOUTHWEST ACROSS SOUTHERN MICHIGAN FROM PARENT CENTER OVER NORTHERN MAINE...WHILE MID LEVEL RIDGE AXIS EXTENDS NORTHEAST INTO MICHIGAN FROM SOUTH CENTRAL PLAINS REGION. NORTHERN MICHIGAN FAR REMOVED FROM ANY ACTIVE WEATHER WITH SOUTHEAST CONUS LOW SHOWING SIGNS OF LIFTING NORTHEAST UP THE EASTERN SEABOARD AND SOUTH CENTRAL CANADA SHORTWAVE AND ASSOCIATED SURFACE LOW MOVING NORTHEAST THROUGH NORTHERN ONTARIO. COLD FRONT EXTENDING SOUTHWEST FROM ONTARIO LOW ACROSS CENTRAL MINNESOTA MARCHING STEADILY EAST...BUT EXCEEDINGLY DRY LOW AND MID LEVEL ATMOSPHERE OUT AHEAD OF THIS FEATURE (LOCAL 00Z SOUNDING HAD PWAT VALUE OF ONLY 0.39 INCHES AND SURFACE OBSERVATIONS SHOW MID 20 TO LOW 30 DEWPOINTS ALL THE WAY DOWN TO THE GULF COAST) RESULTING IN NEARLY CLOUD FREE FRONTAL PASSAGE. FORECAST CONCERNS FOR THE REMAINDER OF THE OVERNIGHT RATHER TRIVIAL AND CENTER ON TEMPERATURES AS WELL AS ONGOING MARINE HEADLINES. TEMPERATURE FORECAST IN THIS TYPE OF DRY AIR REGIME ALWAYS DIFFICULT AND USUALLY CENTER ON AMOUNT OF DECOUPLING IN LOW LEVEL WIND FIELD. CASE IN POINT...OUR SOUTHEAST ZONES WHERE SEVERAL HOUR PERIOD OF NEARLY CALM WINDS HAS ALLOWED TEMPERATURES TO ALREADY DROP INTO THE UPPER 20S TO LOW 30S. WITH PRESSURE GRADIENT EXPECTED TO GRADUALLY STRENGTHEN AHEAD OF APPROACHING COLD FRONT...WOULD EXPECT TEMPERATURES TO BEGIN TO STABILIZE IN THIS AREA. HOWEVER...SEVERAL MORE HOURS OF DECENT RADIATIONAL COOLING STILL POSSIBLE AND WILL MAKE THE APPROPRIATE DOWNWARD ADJUSTMENTS TO TEMPERATURES. ELSEWHERE...FORECASTED LOWS IN THE LOW TO MID 30S APPEAR ON TARGET AS READINGS SLOW TO FALL THIS EVENING GIVEN PERSISTENT SOUTH WINDS. MARINE...00Z NAM-WRF STILL PERSISTENT IN SHOWING 950MB WINDS INCREASING TO 35 TO 40 KNOTS OVER NORTHERN LAKE MICHIGAN AND EASTERN UPPER MICHIGAN DURING THE OVERNIGHT. NOT EXPECTING THESE TYPE OF WINDS AT THE SURFACE WITH RATHER STABLE CONDITIONS OVER THE LAKES (LAKE SURFACE TEMPERATURES OF 7C TO 10C WITH 950MB TEMPERATURES PROGGED AT 5C TO 8C). STILL...FEEL POTENTIAL OF WIND GUSTS APPROACHING SCA THRESHOLD OF 25 KNOTS IS POSSIBLE THROUGH THE EARLY MORNING AND WILL THEREFORE LEAVE GOING ADVISORIES IN TACT. UPDATED ZONES/GRIDS OUT SHORTLY. BOGUTH && .PREV DISCUSSION...ISSUED AT 321 PM EST WED NOV 22 2006 WATER VAPOR IMAGERY REVEALING SW-NE FLOW PATTERN ACROSS THE NRN CONUS EMANATING FROM EASTERN PAC TROUGH COMING ONSHORE ON THE WEST COAST. UPSTREAM...SHORT WAVE WORKING ACROSS SRN MANITOBA THIS AFTERNOON EXPECTED TO REMAIN WELL AWAY FROM THE GREAT LAKES. MEANWHILE...LOW AMPLITUDE RIDGE EVIDENT OVER THE SRN PLAINS NOSING UP INTO THE WESTERN GREAT LAKES WHILE BIG CUTOFF LOW PRESSURE SYSTEM OFF THE SE ATLANTIC COAST. AT THE SFC...HIGH PRESSURE FIXED FROM NEW ENGLAND ACROSS THE GREAT LAKES WHILE LOW PRESSURE MOVING INTO ONTARIO WITH A SFC TROUGH/WEAK COLD FRONT EXTENDING DOWN INTO THE NRN PLAINS. WARM ADVECTION MID AND HIGH CLOUD COVER AHEAD OF THIS SYSTEM CONTINUES TO PERIODICALLY STREAM INTO NRN MICHIGAN. TONIGHT THROUGH THURSDAY NIGHT...LOW AMPLITUDE RIDGE EXPECTED TO HOLD THROUGH THE PERIOD AND PERHAPS EVEN SHARPEN UP A BIT ACROSS THE STATE TONIGHT AND THURSDAY. NRN STREAM SHORT WAVE MOVES BY WELL TO THE NORTH WHILE REMNANTS OF WEAK UPSTREAM SFC TROUGH/WEAK COLD FRONT SLIPS INTO THE NRN PART OF THE STATE ON THURSDAY. NOTHING TO WORK WITH HERE IN TERMS OF AVAILABLE MOISTURE AS AFTERNOON SFC DEWPOINTS ACROSS INTERIOR NRN LOWER MICHIGAN CRASHED INTO THE TEENS... INDICATIVE OF THE DRY ATMOSPHERE. SO OTHER THAN PERIODIC BOUTS OF MID/HIGH CLOUDS MOVING THROUGH TONIGHT...THANKSGIVING HOLIDAY WEATHER LOOKING TO BE DRY AND RELATIVELY MILD. DESPITE DEWPOINTS CRASHING INTO THE TEENS AS MENTIONED ABOVE...STRONGER WINDS ABOVE THE BOUNDARY LAYER WILL KEEP A 5 TO 15 MPH SFC WIND GOING OVERNIGHT AND PREVENT TEMPS FROM CRASHING. HIGH TEMPERATURES ON THANKSGIVING IN THE LOWER AND MIDDLE 50S...A GOOD 10 TO 15 DEGREES ABOVE NORMAL. MARINE...STRONGER WINDS FINALLY BEGINNING TO MATERIALIZE ACROSS UPPER MICHIGAN AND PORTIONS OF LAKE MICHIGAN BUT SO FAR GUSTS ARE WELL BELOW GALE FORCE. 950 MB WINDS ARE FORECAST TO RAMP UP INTO THE 30-40 KNOT RANGE ACROSS LAKE MICHIGAN AND INTO EASTERN UPPER MICHIGAN LATE THIS EVENING...STILL RAISING THE POSSIBILITIES FOR GALE FORCE WIND GUSTS. HOWEVER...OVER WATER STABILITY WILL PLAY A ROLE TONIGHT AS 950 MB TEMPS HEAD INTO THE 5-10C RANGE WHILE LAKE MICHIGAN WATER TEMPS RUNNING 7-10C...A STABLE SCENARIO. GIVEN THIS...PROLONGED GUSTS TO GALE FORCE APPEAR UNLIKELY WITH GUSTS INTO THE MID AND HIGH 20 KNOT RANGE A MORE LIKELY SCENARIO. THUS...AFTER COLLABORATION WITH CHICAGO...WILL CANCEL THE CURRENT GALE WARNINGS WITH THE AFTERNOON NEARSHORE FORECAST ISSUANCE. ADAM LATER PERIODS (FRIDAY ONWARD)...DIFFICULT MEDIUM RANGE FORECAST WITH MODELS IN DISAGREEMENT ON STRENGTH/PLACEMENT OF SHORTWAVES AND ON SOUTHWARD INFILTRATION OF COLD AIR INTO THE GREAT LAKES. LONGWAVE PATTERN BECOMES MUCH MORE AMPLIFIED AS WELL...RESULTING IN RATHER SIGNIFICANT TIMING DIFFERENCES WITH CYCLOGENESIS ACROSS THE CENTRAL PLAINS EARLY NEXT WEEK. SO THE MAIN FORECAST ISSUES CENTER PCPN CHANCES OVER THE WEEKEND AND FROPA FOR THE MIDDLE OF NEXT WEEK. RATHER QUIET AND COMFORTABLE DAY ON FRIDAY WITH 1024MB SURFACE RIDGE AXIS SLIDING EAST OF THE AREA AND WEAKENING SURFACE FRONT SAGGING SLOWLY TOWARD THE WESTERN LAKES. INCREASE IN H8-H5 MOISTURE DURING THE AFTERNOON AHEAD OF THIS FEATURE...SO SUNSHINE FADING BEHIND AFTERNOON CLOUDS. 850MB TEMPERATURES IN THE +6 TO +8 DEGC RANGE...SO ANOTHER WELL ABOVE NORMAL DAY WITH HIGHS IN THE UPPER 40S TO LOWER 50S. LIMITED DYNAMICS AND VERY LITTLE MOISTURE WITH THIS FRONT...SO WILL KEEP THE FORECAST DRY. ON SATURDAY...ISENTROPIC UPGLIDE INCREASES ON THE 300K SURFACE AS WARM AIR ASSOCIATED WITH DEVELOPING SURFACE WARM FRONT BEGINS TO OVERRIDE LOW LEVEL COOLER AIR ACROSS MICHIGAN. LOW LEVELS FAIRLY MOIST />80% H10-H8/ BUT QUITE A BIT OF DRY AIR BETWEEN H8-H5 INITIALLY...SO A MOSTLY CLOUDY DAY WITH ONLY LOW CHANCES OF RAIN IN THE AFTERNOON /MAINLY ACROSS SOUTHERN PARTS OF THE CWA/. WARM FRONT LIFTS SLOWLY NORTH THROUGH THE AREA SATURDAY NIGHT AND SUNDAY AS SURFACE LOW DEVELOPS OVER THE CENTRAL PLAINS. WILL PUT CHANCE POPS IN THE FORECAST FOR BOTH PERIODS. PCPN ALL LIQUID...WITH SURFACE BASED WARM LAYER GREATER THAN 3K IN ALL AREAS. EARLY IN THE WEEK...THE MODELS REALLY BEGIN TO DIVERGE IN THE STRENGTH AND SPEED OF LONGWAVE TROF DEVELOPING OVER THE PLAINS. FIRST COLD FRONT SWEEPS THROUGH THE REGION LATE SUNDAY NIGHT OR EARLY MONDAY. THIS WILL ALLOW COOLER 850MB AIR TO SAG SOUTH INTO THE AREA /H8 TEMPS -1 TO -3 DEGC/. ALL EYES THEN TURN TOWARD DEVELOPING SURFACE LOW OVER THE PLAINS. ARCTIC AIR WILL PLUNGE DOWN THE FRONT RANGE WITH A BIG SNOW EVENT POSSIBLE FOR THE NORTHERN ROCKIES INTO PARTS OF THE DAKOTA/S. BY TUESDAY...SURFACE LOW MOVES TOWARD THE MISSISSIPPI VALLEY DRAWING A WARM FRONT NORTH INTO MICHIGAN. THIS COULD INITIALLY BE A LIGHT MIXED OVERRUNNING EVENT FOR PARTS OF THE REGION...WITH A TRANSITION TO RAIN LATER TUESDAY OR TUESDAY NIGHT. WILL NOT GET TOO DETAILED WITH THINGS THAT FAR OUT...GOING WITH CHANCE RAIN SOUTH OF M-72 ON TUESDAY AND A CHANCE OF RAIN OR SNOW NORTH OF THIS AREA. ARCTIC FRONT IMPACTS THE AREA ON WEDNESDAY. MODELS VARYING BY ABOUT 12 HOURS IN THE SPEED OF FROPA...ALTHOUGH OVERALL TREND IN ALL MODELS HAS BEEN LESS PROGRESSIVE AND MORE AMPLIFIED. THIS FAR OUT...WILL TAKE AN ECWMF/GFS BLEND AND BRING THE FRONT ACROSS THE AREA DURING WEDNESDAY AFTERNOON. THIS FRONT MEANS BUSINESS...AS TEMPERATURES COULD START THE DAY NEAR 50 AND END THE DAY IN THE 20S. THERE WILL ALSO BE A LOT OF WIND...WITH GALES OR EVEN STORMS POSSIBLE ON THE LAKES. COLDER AIR POURS INTO THE AREA FOR THE END OF THE WEEK WITH THE LAKE EFFECT MACHINE GOING IN W/NW FLOW AREAS. JK && .APX...WATCHES/WARNINGS/ADVISORIES...NONE && $$ mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 325 PM EST WED NOV 22 2006 .DISCUSSION... 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW ALF E OF TROF OFF THE W COAST BRINGING MILD PACIFIC AIR TO THE NRN CONUS. 12Z H85 TEMPS APRCHG 15C OVER THE NRN PLAINS...WITH READINGS 5-10C OVER THE CWA THIS MRNG PER LOCAL RAOBS/TAMDAR SDNGS. NOON TEMP ALREADY UP TO 52 AT BARAGA...WITH READINGS APRCHG 50 IN A NUMBER OF OTHER LOCATIONS. FARTHER W...MIXING TO JUST H9 ON BIS SDNG WOULD SUPPORT TMAX IN THE UPR 60S. THESE SDNGS ALSO SHOW A RELATIVELY DRY LOW-MID TROP. THERE IS A BAND OF HI CLD STRETCHING FM THE CNTRL PLAINS INTO THE UPR GRT LKS ON ACYC SIDE OF H3 JET AXIS...BUT 12Z MPX SDNG SHOWS HIER MSTR CONFINED AOA H5. PWAT UPSTREAM AS LO AS 0.15 INCH AT RAP. THERE IS A SHRTWV LIFTING ENEWD THRU SASKATCHEWAN WITH SFC LO NEAR LK WINNIPEG ATTM...BUT AIRMASS IN WARM SECTOR IS SO DRY THERE IS NOT A CLD ON ATTENDANT COLD FNT EXTENDING S INTO SDAKOTA DESPITE FAIRLY SHARP WSHFT ALG THIS BNDRY. ANOTHER SHRTWV EMBEDDED WITHIN TROF OFF THE W COAST IS APRCHG THE PAC NW COAST. ANOTHER SHRTWV NOTED IN THE GLFAK. MAIN FCST CONCERNS THE NEXT FEW DAYS REVOLVE MAINLY ARND TEMPS AS NUMERICAL GUIDANCE SHOWS AN UPR RDG PERSISTING INTO THE GRT LKS THRU THU. FOCUS FOR FRI WL SHIFT TO TIMING/IMPACT OF SHRTWV NOW APRCHG THE PAC NW FCST. FOR TNGT...SHRTWV IN SASKATCHEWAN/ACCOMPANYING SFC LO FCST TO MOVE THRU NW ONTARIO AND REACH A POSITION NR JAMES BAY BY 12Z THU...WITH ATTENDANT COLD FNT PASSING THRU THE CWA BY 12Z. STORM TRACK IS SO FAR TO THE N AND ANTECEDENT AIRMASS SO DRY THERE SHOULD BE NO PCPN AND LTL IF ANY CLD COVER. SUSPECT HI CLD WL CONT TO PLAGUE MAINLY THE SRN ZNS AS BAND OF CI/CS SHOWING SIGNS OF PRESSING SLOWLY SWD THIS AFTN. NAM/GFS SHOW SW H925 WINDS AS HI AS 35-40KTS AHEAD OF THE FNT THIS EVNG GIVING WAY TO A LIGHTER NW FLOW LATER TNGT BEHIND THE FROPA. QUITE A DISCREPANCY ON MOS FCST LO TEMPS TNGT WITH ETA MOS AS MUCH AS 5 TO 10 DEGREES HIGHER THAN GFS MOS AT A COUPLE OF SPOTS. CONSIDERING VERY DRY AIR UPSTREAM AND A FEW MIN TEMP REPORTS IN THE LO/MID 20S THIS MRNG UPSTREAM NR THE FNT...WL TEND TOWARD THE LOWER END OF GUIDANCE OVER THE INTERIOR W WHERE WINDS WL GO LIGHTER BEHIND EARLIER FROPA AND HI CLD WL HAVE LESS OF AN IMPACT. ON THU...FA WL UNDER THE DOMINATION OF SHRTWV RDGING BEHIND DEPARTING SHRTWV...WITH AXIS OF HI PRES EXTENDING S FM CENTER IN NW ONTARIO THRU THE CWA. EXCEPT FOR SOME MAINLY AFTN HI CLD SPILLING OVER APRCHG RDG AXIS...THE DAY SHOULD BE MOSUNNY. SINCE THE HI PRES CENTER WL BE N OF THE CWA...EXPECT A N FLOW VEERING E TO DOMINATE AS THE RDG SLIPS TO THE E. ALTHOUGH THE AIRMASS WL BE A MILD PACIFIC ONE...COMBINATION OF LOWER H85 TEMPS (ARND 7C) AND LIGHT ONSHORE FLOW WL MEAN A COOLER DAY...ESPECIALLY NR LK SUP. OVER INLAND AREAS...MIXING TO H9 ON GFS/NAM FCST SDNGS YIELDS HI TEMPS CLOSE TO THEIR RESPECTIVE MOS FCSTS (ETA MOS HIER THAN GFS MOS). CONSIDERING UPSTREAM WARMTH WITH TEMPS ARPCHG 60 EVEN BEHIND COLD FNT...WL BUMP FCST HI TEMPS UP OVER INLAND AREAS A COUPLE OF DEGREES. ON THU NGT/FRI...SHRTWV NOW APRCHG THE PAC NW AND ACCOMPANYING SFC LO CENTER FCST TO LIFT TO NEAR LK WINNIPEG BY 12Z FRI AND INTO NW ONTARIO BY 00Z SAT. GFS/NAM SHOW SLY WINDS AT H925 INCRSG TO 40-50KTS DURING THU NGT AHEAD OF THE SHRTWV...BUT THIS FLOW APPEARS TO TAP LTL IN THE WAY OF MSTR AS PWAT FCST TO RISE TO JUST A BIT ABV 0.50 INCH. SO DESPITE SOME FAIRLY SHARP ISENTROPIC LIFT...GFS FCST SDNGS SHOW AN ATMOSPHERE PROHIBITIVELY DRY FOR PCPN. SINCE NO MODEL NOW FCSTS MEASUREABLE PCPN OVER THE LAND FA THRU 00Z SAT AND ETA/GFS MOS POPS UNDER 20...WL REMOVE POPS FM THE ENTIRE FA EXCEPT W-N LK SUP. SUSPECT HOWEVER THERE WL BE SOME SC AS GFS/NAM FCST SDNGS SHOW A LYR OF HIER RH H9-85 COINCIDENT WITH THE STRONGER SW FLOW AHEAD OF THE LOW CENTERS ATTENDANT PACIFIC TYPE COLD FNT PROGGED TO MOVE BY DURING THE DAY FRI. OTRW...INCRSG SLY FLOW WL GREATLY DIMINISH DIURNAL FALL OF TEMP THU NGT...SO TENDED TOWARD THE HI END OF MOS GUIDANCE FOR MIN TEMPS. GOING FCST HI TEMPS LOOK TO BE A GOOD COMPROMISE BTWN LOWER GFS/HIER ETA MOS FCST HI TEMPS. PACIFIC HI PRES PROGGED TO BLD IN ON FRI NGT/SAT...SO EXPECT A QUIET...MILD TIME WITH NOTHING BUT SOME HI CLDS...ESPECIALLY OVER THE SRN TIER CLOSER TO WHERE GFS SHOWS FNT STALLING OUT. GFS FCST SDNGS SHOW TOO MUCH MID LVL DRY AIR TO SUPPORT ITS LGT QPF JUST TO THE S. TRENDED ON THE LOWER SIDE FOR MIN TEMPS FRI NGT WITH LGT WINDS/BUBBLE HI/MID LVL DRYING...SO ADDED SOME PTCHY FOG OVER THE INTERIOR TO ACCOUNT FOR GOOD RADIATION CONDITIONS. GOING FCST HI TEMPS LOOK RSNBL FOR SAT. MEDIUM/EXTENDED RANGE GUIDANCE CONTINUES TO ADVERTISE TREND FM ECNTRL NAMERICA RDG TO TROF NEXT WEEK AND RETURN OF MORE SEASONABLY CHILLY AIR TO UPPER MI. SHRTWV THAT IS FCST TO BEGIN TRANSITION IS CURRENTLY IN THE GLFAK. THIS SYS FCST TO EJECT OUT OF WRN TROF ON SAT AND MOVE THRU THE NRN PLAINS/NW ONTARIO TO THE NW OF THE UPR LKS ON SUN. CONSIDERABLE TIMING DIFFERENCES NOTED BTWN FASTER GFS/SLOWER ECMWF...WL TREND TOWARD MORE CONSISTENT ECMWF AND NCEP MANUAL GUIDANCE. SINCE FA WL BE IN JET SURGE REGION OF THIS SHRTWV AND MSTR WL BE LIMITED...SUSPECT PCPN AMTS WL BE ON THE LGT SIDE. PCPN TYPE SHOULD BE ALL RA WITH PACIFIC AIRMASS IN PLACE BEFORE LO ARRIVES AND ECMWF SHOWING H85 TEMP RISING TO 5C BY LATE SUN IN THE ACCOMPANYING LOWS WARM SECTOR. EXPECT A COLDER DAY ON MON IN THE WAKE OF THIS SYS...BUT LES SHOULD BE LIMITED BY SHALLOW NATURE OF COLD AIR (H85 TEMP FCST TO FALL TO NO LOWER THAN -8C)/MORE ACYC FLOW THAT FOLLOWS THE LO. ANOTHER POWERFUL SHRTWV FCST TO LIFT THE ENTIRE WRN TROF OUT IN THE TUE/WED TIMEFRAME. ALL MODELS NOW SHOW DEEP LO MOVING NE TOWARD THE GRT LKS ON TUE AND THEN INTO ONTARIO ON WED. PCPN TYPE WL BE DIFFICULT TO PIN DOWN ATTM...BUT A MIX APPEARS LIKELY WITH OVRRNG OF SHALLOW COLD AIR MASS BEGINNING MON NGT. SOME GUIDANCE... ESPECIALLY THE 00Z/06Z GFS...SHOWS SFC LO GOING FAR ENUF TO THE W THAT TUE WOULD BE A RAINY DAY WHILE ECMWF HINTS THAT AIRMASS WOULD BE COLD ENUF FOR ALL SN THRU THE DAY. 00Z CNDN MODEL/NCEP GUIDANCE SHOWS SFC LO TRACKING RIGHT THRU THE CNTRL U.P. AND WL USE COMPROMISE SOLN AS A MODEL. THIS SOLN WOULD SUG MAINLY SN OVER THE W WITH A MIX ACRS THE CNTRL AND E. THEN WINDY AND COLDER ON WED WITH SYNOPTIC PCPN TRENDING TOWARD LES. COORDINATED WITH GRB. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ KC mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1029 AM EST WED NOV 22 2006 .DISCUSSION... THE MAIN CONCERN WITH THIS UPDATE IS WITH THE HIGH TEMPERATURE POTENTIAL FOR THIS AFTERNOON. WATER VAPOR IMAGERY AND RUC SHOWING A DEEP CLOSED LOW OVER SOUTHEASTERN CONUS AND A ZONAL FLOW OVER SOUTHEASTERN CANADA. WEAK SHORTWAVE RACING ALONG THE FLOW ACROSS SOUTHERN CANADA ARE SHOWING UP OVER MONTANA...SOUTH DAKOTA...AND THE FORECAST AREA. SURFACE ANALYSIS INDICATES A RIDGE OVER THE LOWER GREAT LAKES AND THE NEW ENGLAND STATES. A CLOSED LOW IS OVER LAKE WINNIPEG...WITH A TROUGH STRETCHING SOUTH THROUGH THE NORTHERN PLAINS. THE EAST COAST RIDGE IS DIVERTING THE MANITOBA LOW EAST NORTHEAST TOWARDS JAMES BAY. THE ASSOCIATED TROUGH WILL EDGE INTO NORTHWEST MINNESOTA BY LATE AFTERNOON. FLOW AHEAD OF THE TROUGH WILL KEEP A SOUTHWEST FLOW OVER THE UPPER GREAT LAKES THIS AFTERNOON. THE SHORTWAVE OVER THE FORECAST AREA WILL SHIFT INTO ONTARIO THIS AFTERNOON...WHILE THE SOUTH DAKOTA SHORTWAVE WILL RACE INTO MINNESOTA. THE AIR MASS IS FAIRLY DRY...LESS THAN 50 PERCENT BELOW 500MB...OVER THE FORECAST AREA. SURFACE WINDS WILL REMAIN OUT OF THE SOUTHWEST THIS AFTERNOON. TRAJECTORY PROGS INDICATE THE AIR MASS OVER IOWA YESTERDAY WILL ADVECT INTO THE FORECAST AREA. WRF/RUC MODEL CONTINUE TO KEEP A DECK OF CLOUDS BETWEEN 550MB-450MB THROUGH MOST OF THE AFTERNOON. THIS SHOULD LIMIT HEATING WHICH SHOULD OFF SET SOME OF THE WARMING DUE TO ADVECTION. IR IMAGERY SUPPORTS THIS WITH CLEARING FROM THE WEST THIS BY LATE AFTERNOON. WITH HEATING THIS AFTERNOON...WINDS WILL PICK UP A BIT AS SOME OF THE LOW LEVEL JET WILL BE MIXED TO SURFACE. THIS INCREASE WINDS WILL LIMIT HEATING AS WELL. GUIDANCE INDICATES WARMER TEMPERATURES OVER THE WEST BY LATE AFTERNOON. AT 15Z GUIDANCE IS FAIRLY CLOSE TO ACTUAL. THUS THIS LOOKS REASONABLE. FOR NOW WILL STAY WITH GUIDANCE. DO NOT PLAN TO DO UPDATES AT THIS TIME. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DLG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 820 PM EST WED NOV 22 2006 .SHORT TERM /TONIGHT/...MOST RECENT GUIDANCE COMING IN A FEW DEGREES WARMER OVERNIGHT ALONG THE COASTAL PLAIN AND ALONG THE COAST. RAISED TEMPS IN THOSE AREAS AND JUST ISSUED NEW ZONE PACKAGE. DISTRIBUTION OF RAIN CHANCES STILL LOOKS VERY GOOD BASED ON RADAR LOOP AND RUC40. && .AVIATION...IFR CIGS HAVE DEVELOPED AT ALL THE TAF SITES THIS EVENING. NAM-12 SOUNDINGS HAVE DEPICTED THE SATURATED LOW LEVELS VERY WELL AND INDICATE A LOWERING OF BASES TO LIFR AFT 06Z. I DECIDED TO KEEP PREDOMINATE IFR CIGS ALL NIGHT AND MAY LOWER TO LIFR FOR THE 06Z TAFS. PCPN ASSOCIATED WITH LOW PRESSURE REDEVELOPING OFFSHORE IS PRIMARILY ALONG THE COAST BUT IS FORECAST TO BE BECOME MORE WIDESPREAD BETWEEN THE KEWN-KORF TWEB LEG. I INITIALLY UNDERPLAYED PCPN IN THE 00Z TAFS BECAUSE I WANTED TO GET A BETTER HANDLE ON THE EVOLUTION OF THE DEVELOPING PCPN AREA. I WILL LIKELY UPDATE THE TAFS AFTER 03Z TO INDICATE A PREDOMINATE PCPN GROUP. && .MARINE...TIGHT PRESSURE GRADIENT HAS MOVED JUST NORTH OF THE NC WATERS WHERE GALE FORCE WINDS CONTINUE TO BLOW. WINDS HAVE RELAXED TO 10-15 G20 KT. THE SFC LOW HAS REFORMED OFF THE NC COAST AND WILL DRIFT SLOWLY NE DURING THE NEXT 24 HOURS WHEN IT SHOULD FINALLY BE NE OF THE WATERS BY THURSDAY EVENING. EASTERLY SWELLS STILL ABOVE SCA CRITERIA AND WILL REMAIN HIGH THROUGH FRI. AS THE SFC LOW PULLS AWAY THU AFTERNOON THE FLOW WILL COME AROUND TO THE N AND NW AND INCREASE BACK TO SCA LEVELS...ESPECIALLY NORTH OF HSE WHERE WINDS MAY BRIEFLY REACH GALE FORCE LATE IN THE DAY. THE CURRENT FORECAST IS IN GOOD SHAPE AND WILL NEED ONLY MINOR TWEAKING THIS EVENING. NO CHANGES TO HEADLINES WHERE SCA WILL CONTINUE. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 12 PM THURSDAY TO 1 AM EST FRIDAY FOR AMZ130-135. SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR AMZ150-152-154- 156-158. && $$ SHORT TERM...AUSTIN AVIATION...ELARDO MARINE...ELARDO nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1046 AM EST WED NOV 22 2006 .SHORT TERM /REST OF TODAY/... HEAVY RAIN CONTINUING OVER THE EASTERN PORTIONS OF THE CWFA. THIS RAIN WILL CONTINUE INTO THE EARLY AFTERNOON. 12Z RUC AND NAM SHOW AXIS OF HEAVY RAIN PIVOTING AROUND UNION COUNTY NC DURING THIS TIME. COULD BE UP TO ANOTHER 2 INCHES OVER OUR EXTREME SOUTHEASTERN COUNTIES BEFORE ENDING. THE GOOD NEWS IS THE BAND OF HEAVY RAIN MOVING INTO THE AREA IS SHRINKING AS DRIER AIR WRAPS AROUND THE OCCLUDED UPPER LOW. HOPEFULLY THIS WILL KEEP THE ALREADY EXCESSIVE RAINFALL FROM BECOMING EXTREME. WILL KEEP FLOOD WATCH AS IS EVEN THOUGH FLOODING IS LESS LIKELY OVER THE WESTERN PORTIONS OF THE WATCH. DO NOT WANT TO CLEAR ANY COUNTIES WHEN A HEAVY RAIN BAND IS STILL EXPECTED TO MOVE THROUGH. HAVE ADJUSTED POPS TO REFLECT CURRENT AND EXPECTED CONDITIONS. WINDS HAVE DIMINISHED ACROSS THE WEST. EXPECT THEM TO COME BACK UP SOME WITH MIXING. WINDS STILL UP OVER THE EAST SO WILL LEAVE LAKE WIND ADVISORY IN EFFECT. TEMPS ALREADY NEAR FORECAST HIGHS OVER THE WEST WHERE LITTLE RAINFALL AND EVEN SOME SUNSHINE HAVE OCCURRED. EVEN WHERE RAIN IS FALLING...TEMPS ARE NEAR HIGHS. HAVE RAISED HIGHS IN THE WEST AND A DEGREE OR TWO IN THE EAST. && .PREV DISCUSSION... /ISSUED 258 AM EST WED NOV 22 2006/ SHORT TERM /TODAY THROUGH THURSDAY NIGHT/... THE FIRST ORDER OF BUSINESS THIS MORNING WILL BE TO CANCEL THE FREEZING RAIN ADVISORY FOR THE NORTHERN NC MTNS. SUPPLEMENTAL OBS INDICATE TEMPS OVER AVERY COUNTY HAVE INCREASED TO WELL ABOVE FREEZING...AS STRONG WAA HAS FINALLY KICKED IN OVER THE MTNS. THERE MAY BE ISOLATED POCKETS OF FREEZING TEMPS...MORE THAN LIKELY IN SHELTERED VALLEYS...BUT THE THREAT ISNT SUFFICIENT ENOUGH TO KEEP THE ADVISORY GOING. OTHERWISE...MODERATE TO HEAVY PRECIP CONTINUES TO WRAP INTO THE PIEDMONT THIS MORNING W/IN DEFORMATION ZONE NORTH OF MID/UPPER LEVEL LOW. WE HAVE ALREADY SEEN FAIRLY WIDESPREAD 1-2 INCH RAINFALL AMOUNTS ALONG THE I-77 CORRIDOR...WITH SOME SPORADIC FLOODING... MAINLY IN THE CHARLOTTE METRO AREA. AS THE UPPER LOW CONTINUES TO CHURN ITS WAY SLOWLY NORTH...THE THREAT FOR HEAVY RAIN WILL PERSIST IN THESE AREAS THROUGH AT LEAST THE MORNING HOURS...AND WOULDN/T BE SURPRISED TO SEE ADDITIONAL AMOUNTS OF 1-2 INCHES BEFORE ALL IS SAID AND DONE. A FLOOD WATCH WAS ISSUED FOR THE I-77 CORRIDOR EARLIER... AND DO NOT PLAN TO MAKE ANY CHANGES TO THIS ATTM. WINDS WILL ALSO BE A BIT OF A CONCERN TODAY AS WELL...WITH STRONG COASTAL LOW PRODUCING ABOUT AN 8 MB GRADIENT ACROSS THE CWFA...AND A 50 KT LOW LEVEL JET INDICATED ON VAD WIND PROFILES...AND ON THE SPECIAL 06Z SOUNDING FROM GSO. WE WILL EXTEND THE LAKE WIND ADVISORY THROUGH THE DAY AND EXPAND IT TO CAPTURE A LARGER PORTION OF THE CWFA. EARLIER CALLS TO SOME OF THE COUNTIES INDICATED A FEW TREES WERE FALLING HERE AND THERE DUE TO THE COMBINATION OF WIND AND WET GROUND...SO WILL RE-ISSUE THE SPS TO ADDRESS THIS POTENTIAL AS WELL. THE MODELS ARE IN GENERAL AGREEMENT THAT PRECIP ASSOCIATED WITH THE UPPER LOW SHOULD LIFT NORTHEAST OF THE AREA THIS EVENING...SO WILL ONLY CARRY SLIGHT CHANCE POPS ACROSS THE EASTERN ZONES DURING THE 2ND PERIOD. THE REMAINDER OF THE SHORT TERM WILL BE DRY AND RATHER WARM...AS A FULL LATITUDE UPPER RIDGE BECOMES POSITIONED OVER THE EASTERN CONUS. LONG TERM /FRIDAY THROUGH TUESDAY/... DEEP LAYERED RIDGING PROGGED TO BE IN CONTROL OF OUR WEATHER FOR FRIDAY AND SATURDAY RESULTING IN CONTINUED DRY WEATHER AND MAX TEMPERATURES REBOUNDING TO ABOVE NORMAL READINGS. THE WEATHER PATTERN WILL BECOME FLATTER SUNDAY THRU MONDAY...BUT LOW AMPLITUDE RIDGING IS PROGGED TO LINGER OVER THE SOUTHEAST U.S. SO...SENSIBLE WEATHER FCST FOR THIS PERIOD WILL REMAIN DRY AND MILD. INCREASING WAA PATTERN DEVELOPS BY NEXT TUESDAY OUT AHEAD OF APPROACHING VIGOROUS STORM SYSTEM WHICH COULD BRING SHOWER CHANCES INTO THE REGION BY DAY 7. AVIATION... RADAR IMAGERY SHOWS A LARGE AREA OF PRECIP WRAPPING WESTWARD ACROSS THE PIEDMONT AROUND THE N SIDE OF THE OCCLUDED LOW. EXPECT MVFR VISIBILITY TO BE A CONCERN AT KCLT FOR THE NEXT SEVERAL HOURS... REALLY THROUGH THE MIDDLE PART OF THE DAY...WITH OCCASIONAL IFR VIS IN HEAVIER PRECIP. MVFR CEILINGS WILL ALSO PREVAIL AT KCLT...AND THE LOW CEILING SHOULD MOVE WESTWARD TO UPSTATE SC AS WELL...SO BOTH KAND AND KGSP SHOULD HAVE AT LEAST OCCASIONAL MVFR CLOUDS. THE FORECAST LOOKS GRIM FOR THE BETTER PART OF THE DAY WITHOUT MUCH CHANGE AS THE LOW MOVES SLOWLY N. THINK THE LOW CLOUD CEILINGS WILL NOT BREAK UP UNTIL THE LATE PART OF THE AFTERNOON...BUT SHOULD SCATTER OUT QUICKLY THIS EVENING AS THE LOW PULLS AWAY. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...FLOOD WATCH FOR NCZ035>037-056-057-068>072-082 UNTIL 6 PM WEDNESDAY. ...LAKE WIND ADVISORY FOR NCZ035>037-053-056-057-064>072-082- 507>510 UNTIL 6 PM WEDNESDAY. SC...LAKE WIND ADVISORY FOR SCZ003-006>009-014 UNTIL 6 PM WEDNESDAY. ...FLOOD WATCH FOR SCZ008-009-013-014 UNTIL 6 PM WEDNESDAY. && $$ SHORT TERM...RWH sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 1015 AM EST WED NOV 22 2006 .SHORT TERM /TODAY/...MSAS CURRENTLY SHOWS THE CENTER OF THE STRONG COASTAL LOW STRADDLING THE NC COAST BETWEEN THE ILM AND MHX CWFA/S WHICH MATCHES UP WELL WITH A WRF/RUC BLEND. THE UPR LVL LOW IS CENTERED ALONG THE SC COAST BETWEEN SAVANNAH AND BEAUFORT AS DEPICTED ON WV IMAGERY...WHICH THE RUC HANDLES A BIT BETTER THAN THE WRF SO WILL RUN WITH THE RUC FOR THE SHORT-TERM DETAILS. HAVE SEEN A MOD/HVY RAIN SHIELD SLOWLY SHIFT SWWD ACRS THE SC MIDLANDS AND MAKE INROADS TO FAR NWRN PORTIONS OF THE CWFA. MEANWHILE...SCT SHOWERS HAVE DEVELOPED ALONG THE SRN SC COASTAL PLAIN. BOTH THE WRF AND RUC SHOW WRAP-AROUND MOISTURE SPREADING OVR MUCH OF SRN SC AND SLIGHTLY PAST THE SAVANNAH RIVER...BUT RUC KEEPS BEST PRECIP CLOSER TO CENTRAL SC WHICH MATCHES UP BETTER TO CURRENT KCLX RADAR TRENDS SO HAVE OPTED TO KEEP CATEGORICAL POPS GOING OVR FAR NRN AND WRN PORTIONS OF THE CWFA WITH LIKELY POPS GOING FURTHER S. PRECIP LOOKS TO STEADILY THIN OUT DURG THE DAY SUCH THAT BY LATE AFTN LIKELY POPS SHOULD SUFFICE N AND CENTRAL WITH HIGH CHC POPS S. HAVE INCRD THE QPF A BIT SEEING THE HEAVY RAINS THAT THE CAE AND ILM CWFA/S HAVE BEEN RECEIVING FROM THE STRONG PRECIP SHIELD AND CONFINED THOSE HIGHER QPF VALUES TO FAR N AND W PORTIONS OF THE CHS CWFA. TEMPS WILL AGAIN BE TRICKY AS SOME LOCATIONS HAVE ALREADY REACH ADVERTISED HIGHS WHILE OTHERS ARE ABOUT 5-7 DEGREES OFF. WILL GENERALLY LOOK FOR TEMPS TO REACH THE UPR 40S TO LOWER 50S SO ONLY MINOR TWEAKS WERE MADE TO THE TEMP CURVE. WINDS HAVE NOT BEEN AS IMPRESSIVE AS ORIGINALLY THOUGHT...SO WILL TWEAK DOWN WIND SPEEDS BUT STILL LOOK FOR SPEEDS IN THE 10 TO 15 MPH RANGE...POSSIBLY UP TO 20 ALONG THE COAST. && .MARINE...SFC LOW PRES CENTER NOW JUST OFF THE NC/SC BORDER...MOVING SLOWLY N. WINDS ACROSS OUR WATERS HAVE DECREASED SIGNIFICANTLY EARLY THIS MORNING. SUSTAINED WINDS OF 10-20 KT WITH GUSTS AS HIGH AS 28 KT ARE THE RULE ATTM. SEAS HAVE ALSO BEEN SUBSIDING QUITE A BIT...ESPECIALLY IN THE NEARSHORE DUE TO A MORE NLY SWELL COMPONENT AND SOLID OFFSHORE FETCH. PRES GRAD SHOULD REMAIN FAIRLY CONSTANT THROUGH THIS AFTN WITH ONLY A SLIGHT INCREASE IN WINDS DUE TO INCREASING CAA. CANNOT JUSTIFY THE ONGOING GALE WARNINGS FOR ALL THE WATERS WITH CURRENTLY FCST WINDS. PLAN TO DOWNGRADE THE GALES TO SMALL CRAFT ADVISORIES ALL AREAS. THE SCA FOR THE OUTER GA WATERS WILL EXTEND THROUGH 00Z MON DUE TO CONTINUED SEAS AS HIGH AS 6 FT OVER THE OUTER PORTION. THIS FLAG WILL NEED TO BE TRANSITIONED TO A SCA FOR HAZ SEAS AT SOME POINT WHEN THE WIND CRITERIA ARE NO LONGER BEING MET. && .COASTAL IMPACTS...BUOY DATA SHOWS THE SWELL COMPONENT HAS DECREASED SIGNIFICANTLY THIS MORNING ACROSS OUR WATERS. HEIGHTS BETWEEN 3 AND 5 FT ARE FAIRLY COMMON...BUT THE DOMINANT SWELL DIRECTION IS MORE NNE NOW RATHER THAN NE OR ENE. THIS SEEMS TO BE PREVENTING MUCH OF THE SWELL FROM REACHING THE SC COASTLINE. CALLS TO A FEW SC COASTAL LOCATIONS INDICATES WAVES IN THE SURF ZONE ARE 3 FEET AT THE VERY HIGHEST...WITH MORE PREDOMINANT 2 FOOTERS. THE CONTINUED OFFSHORE FLOW TODAY SHOULD NOT LEND TO ANYTHING ANY HIGHER DEVELOPING...THUS WILL CANCEL THE HIGH SURF ADVISORY WITH THE MORNING UPDATE. && .LAKE WINDS...NORTH WINDS AROUND 16 KT WITH GUSTS TO 21 KT CONTINUE ON LAKE MARION. WINDS ON THE OPEN LAKE ARE PROBABLY A BIT HIGHER DUE TO THE SENSOR SAMPLING ONLY WINDS COMING OFF THE LAND. WEAK CAA TODAY MAY RESULT IN A SLIGHT INCREASE IN WIND SPEEDS THIS AFTERNOON. PLAN TO LEAVE THE LAKE WIND ADVISORY IN PLACE AS CURRENTLY ADVERTISED. && .AVIATION...WIND SHEAR...LOW CIGS AND TIMING OF ANY REDUCED VSBYS IN RAIN WILL CONTINUE TO BE THE MAIN FCST CHALLENGES WITH THE MORNING SET OF TAFS. IT SEEMS THAT THE CAA HAS SHUT OFF ENOUGH...WITH EVEN WAA ACROSS THE CHS TERMINAL...THUS SURFACE WINDS ARE RELATIVELY LIGHT THIS MORNING...AND HAVE INCLUDED WIND SHEAR THRU 12Z WITH STRONG 30 KT WINDS AT 2K FT. IF DAYTIME WINDS FAIL TO MATERIALIZE AS NOW IN THE FCST WE MAY NEED TO EXTEND THE WIND SHEAR FCST. BY LATE TODAY AND TONIGHT THE SURFACE WINDS WILL HAVE COME DOWN ONCE AGAIN...LEADING TO WIND SHEAR LATE IN THE FCST PERIOD. WILL FCST IFR OR MVFR CIGS THRU THE FCST PERIOD...WITH POTENTIAL FOR OCNL MVFR VSBYS IN RAIN THRU AT LEAST 18Z. PRECIP WILL LINGER AT BOTH SITES THRU THE DAY TODAY...THEN EVENTUALLY TAPER OFF LATE TODAY AND TONIGHT. BASED ON RECENT SATELLITE AND RADAR TRENDS...MAY NEED TO GO WITH LOWER VSBYS AT SAV THE NEXT FEW HOURS WITH HEAVY RAINS APPROACHING FROM THE N. WILL MONITOR AND AMEND AS NEEDED. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...LAKE WIND ADVISORY FOR SCZ045 UNTIL 10 PM TONIGHT. MARINE...SMALL CRAFT ADVISORY AMZ330-350-352-354-374. && $$ JPC/JRL sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 1248 PM EST WED NOV 22 2006 .AVIATION /18Z-18Z/... RAIN SHIELD NOW ACROSS MOST LOCATIONS WEST OF THE BLUE RIDGE WITH A TREND TOWARDS SLOWER PROGRESSION WESTWARD. CEILINGS IN MOST AREAS WITH THE RAIN HAVE FALLEN TO MVFR LEVELS AND EXPECT THESE LEVELS TO CONTINUE INTO THE EVENING. AS THE PRECIPITATION COMES TO AN END THROUGH THE EVENING AN INCREASE TO LOW END VFR IS PROBABLE. WEST OF THE BLUE RIDGE PRECIPITATION WILL BE MORE PATCHY WITH CEILINGS STAYING VFR IN MOST LOCATIONS. COULD BE A NEAR SURFACE ICING LAYER THAT DEVELOPS AROUND THE 900 MB LEVEL AS TEMPERATURES ALOFT COOL TO THE WET BULB TEMPERATURE WHICH AT THAT LEVEL THIS MORNING WAS AROUND 0 C. STRONG WINDS NOT TOO FAR OFF THE SURFACE WILL CONTINUE INTO THE EVENING HOURS...SO WHERE SURFACE WINDS ARE NOT GUSTY...ANTICIPATE LOW LEVEL WIND SHEAR. BY THURSDAY MORNING...WINDS IN ALL AREAS SHOULD COME AROUND TO THE NORTHWEST WITH DRIER AIR MOVING INTO THE REGION. && .PREV DISCUSSION... /ISSUED 1053 AM EST WED NOV 22 2006/ SHORT TERM /REST OF TODAY/... MORNING UPDATE WILL REFLECT ADJUSTMENTS TO THE TREND OF THE PROGRESSION OF DEFORMATION ZONE RAIN ASSOCIATED ON THE NORTHWEST SIDE OF THE MAIN UPPER LOW. LATEST MODEL GUIDANCE SUGGESTS A PROGRESSION OF THE BULK OF THE RAIN NO FARTHER WEST THEN ABOUT THE CREST OF THE BLUE RIDGE...WITH LIMITED PRECIPITATION WEST OF THAT AREA. WILL BE A VERY FINE LINE BETWEEN AREAS THAT DO RECEIVE RAIN AND THOSE THAT DO NOT. VERY LIMITED...IF ANY...PATCHES OF RAIN JUST WEST OF THE MAIN AREA OF RAIN ARE EXPECTED. BUT SINCE I AM NOT PREPARED TO HAVE A BINARY FORECAST WITH A CLEAR CUT LINE OF 100 PERCENT RAIN NEXT TO AN AREA WITH ZERO PERCENT RAIN...I WILL CONTINUE WITH A FAIRLY TIGHT GRADIENT OF PRECIPITATION CHANCES RANGING INTO THE LIKLEY AND CHANCE CATEGORIES. BUT I WILL SHIFT THE CENTER OF THIS GRADIENT EASTWARD AS COMPARED TO THE EARLIER POSITION. NOW THE EDGE OF THE LIKELY POPS WILL BE NEAR THE CREST OF THE BLUE RIDGE...WITH THE CHANCE CATEGORY FOLLOWING CLOSE TO THE I-81 CORRIDOR. EVEN THE NEWEST GUIDANCE HAS DROPPED THE BALL BY NOT INITIALIZING DEW POINTS IN THE TEENS ACROSS PORTIONS OF THE NEW RIVER VALLEY WHERE THEY ARE CURRENTLY BEING EXPERIENCED. HAD WONDERING IF WHEN RAIN ARRIVES WE WOULD SEE A GENEROUS DROP IN TEMPERATURE TOWARDS THE WET BULB TEMPERATURE AND AS SUCH HAVE A BRIEF PERIOD OF A MIX OF WINTRY PRECIP. HOWEVER...IN ANALYZING THE 12Z KFCX SOUNDING THERE IS ONLY A VERY NARROW LAYER OF AIR WITH WET BULB TEMPERATURES RIGHT AT 0 C WITH THE REST OF THE SOUNDING HAVING BOTH TEMPERATURES AND WET BULB TEMPS ABOVE FREEZING. THIS WITH ONLY MINIMAL PRECIPITATION EXPECTED TO REACH THIS AREA...DO NOT EXPECT ANY WINTRY CONCERNS AND WILL KEEP PRECIPITATION RAIN ONLY. OTHER ADJUSTMENTS HAVE BEEN TO WARM HIGH TEMPERATURES IN THE WEST A BIT. CLOUD COVER THERE SHOULD REMAIN ON THE THIN SIDE HELPING TEMPERATURES TO INCREASE MORE THAN ELSEWHERE ACROSS THE REGION...AND ALSO HAVE WARMED TEMPERATURES IN THE NORTH CAROLINA FOOTHILLS WHERE CURRENT CONDITIONS WERE ALREADY MILDER THAN THE PREVIOUSLY EXPECTED HIGH TEMPS. PREV DISCUSSION... /ISSUED 635 AM EST WED NOV 22 2006/ AVIATION /11Z-06Z/... RAIN HAS MOSTLY MOVED OUT OF THE SERVICE AREA FOR THE TIME BEING...HOWEVER LOOK FOR A RE-DEVELOPMENT OF THE RAIN AND A LOWERING OF CIGS DURING THE DAY FROM ROA EAST. PREVAILING CONDITIONS SHUD REMAIN AT MVFR OR BETTER THRU THE NEXT 24 HOURS. STRONG NE WINDS ALOFT WILL CREATE LLWS CONDITIONS AT BLF AND LWB WHERE SFC WINDS ARE LIGHT. AT ROA/LYH/DAN LLWS WILL BE LESS OF PROBLEM DUE TO STRONGER WINDS AT THE SFC...BUT STILL EXPECT 40-60 KT WINDS FROM 2K FT AND UP. PREV DISCUSSION... /ISSUED 258 AM EST WED NOV 22 2006/ SHORT TERM /TODAY THROUGH FRIDAY/... CLOSED UPR LOW CRNTLY OFF THE GEORGIA COAST STATIONARY OVER THE PAST FEW HOURS. RAINFALL SPREADING WEST TO THE MTNS DURING THE EVENING HOURS IS STARTING TO DIMINISH ON THE NORTHWEST END AS DRY AIR GETS PULLED INTO THE SYSTEM FROM THE NORTHEAST. WETBULB TEMPS ARE BELOW FRZG IN THE WEST THIS MORNING WHICH COULD RESULT IN FRZG RAIN...HOWEVER BELIEVE AT THIS POINT THAT ANY PCPN WILL BE TOO LIGHT TO PUSH TEMPS DOWN THAT LOW...ESP BASED ON CRNT RADAR TRENDS. RAINFALL RATES EARLIER IN THE EVENING WERE A LITTLE WORRISOME DOWN ALONG THE NC/VA LINE HOWEVER THOSE RATES HAVE LIGHTENED UP QUITE A BIT SINCE THEN...TO ARND 0.10 INCH PER HOUR...SO THINK FLOODING THREAT WILL REMAIN SUPPRESSED TO OUR SOUTH. NE SFC WINDS ARE GUSTING TO 25-30 KTS AT TIMES. THIS MAY INCREASE SOMEWHAT DURING THE DAY AS GRADIENT TIGHTENS...BUT SHUD REMAIN WELL BELOW ADV CRITERIA FOR OUR AREA. AS THE UPR LOW MOVES NORTH LATER TODAY AND TNGT ANOTHER SURGE OF RAIN WILL LIKELY WRAP ARND THE NORTH END OF THE LOW AND SPREAD WEST ACROSS MUCH OF THE FCST AREA BEFORE THE SYSTEM PULLS OUT. MODELS NOW IN MUCH BETTER AGREEMENT IN PULLING THE SYSTEM OUT OF SW VA BY THURSDAY AFTERNOON. AFTERWHICH MILD HIGH PRESSURE MOVES OVER THE SOUTHERN APPS/MID-ATLANTIC REGION TO PRODUCE A VERY TRANQUIL WEEKEND. PREV DISCUSSION... /ISSUED 1247 AM EST WED NOV 22 2006/ AVIATION /06Z-06Z/... STRONG UPPER LOW OVER THE SOUTHEAST COAST OF THE U.S. WILL SEND RAIN TO MOST AREAS MAINLY EAST OF THE BLUE RIDGE THIS PERIOD. CIGS WILL DROP TO MVFR ACROSS THE BLUE RIDGE BY 08Z...WITH MVFR CONDITIONS PREVAILING FURTHER EAST AT KLYH AND KDAN THROUGH MIDDAY...AND EVEN LONGER AT DANVILLE. APPEARS LYH MAY BREAK OUT FOR A LIMITED TIME DURING THE EARLY AFTN. FURTHER WEST INTO SE WV...THE RAIN SHOULD HOLD OFF...AS THE SYSTEM WILL BE WOUND UP TIGHTLY KEEPING A SHARP GRADIENT IN PRECIP SHIELD. LEWISBURG SHOULD REMAIN VFR THIS PERIOD...BUT AS THE UPPER LOW STARTS MOVING NORTH TO THE OUTER BANKS...A LOWER MVFR CLD SHIELD SHOULD MOVE INTO LWB AROUND 03Z. PREV DISCUSSION... /ISSUED 935 PM EST TUE NOV 21 2006/ UPDATE... BASICALLY FOLLOWED TREND OF EARLIER UPDATE WITH HIGHER POPS AND WINDS GRIDS IN THE SOUTHEAST. FOLLOWED WRF-RUC PCPN FCST WITH HIGHEST QPF NEARING 1 INCH OVER THE OVER THE SE BY 18Z. 02Z RAINFALL AMOUNTS HAVE REACHED 0.48" AT CASWELL RAWS AND 0.37" AT DANVILLE ASOS. MID SHIFT WILL HAVE TO KEEP CLOSE EYE ON PCPN TRENDS AS RAH HAS PUSHED FLASH FLOOD WATCH TO OUR SE BORDER. RAISED OVERNIGHT MINS AS CLOUDS/WIND WILL OFFSET ANY DYNAMIC COOLING FROM ANY PCPN. PREV DISCUSSION... /ISSUED 715 PM EST TUE NOV 21 2006/ UPDATE... RAISED RAIN POPS IN THE EAST IN RESPONSE TO CURRENT RADAR TRENDS. INSERTED CHC OR SLIGHT CHC OF ZR OR IP IN THE WESTERN VALLEYS AS BUFKIT SOUNDINGS SHOW MIXED PRECIP PSBL AND DYNAMIC COOLING MAY BE A FACTOR AS TDS REMAIN VERY LOW. HOPEFULLY STRONG ENE FLOW WILL SCOUR OUT ANY TRAPPED VALLEY AIR AND ONSET OF CLOUDS AROUND SUNSET SHOULD LESSEN TRAPPED COLD AIR ISSUE. PREV DISCUSSION... /ISSUED 649 PM EST TUE NOV 21 2006/ AVIATION /00Z-24Z/... CUT-OFF LOW OFF THE SE COAST WILL REMAIN NEARLY STATIONARY THROUGH THE PERIOD. WITH ABUNDANT DRY AIR IN PLACE...RAIN SHIELD TRYING TO MOVE TO THE WEST BUT RAIN ONLY REACHING THE GROUND IN SOUTHSIDE VA (23Z TUE). SHORT WAVES ROTATING AROUND THIS LOW WILL BRING PERIODS OF RAIN TO AREAS EAST OF THE BLUE RIDGE OVERNIGHT...PARTICULARLY THE PIEDMONT REGION OF SOUTHSIDE VA AND NORTHWESTERN NC. RAIN BANDS COULD BECOME INTENSE WHICH IN TURN WILL LOWER VISIBILITIES AS 55-65 KT LOW LEVEL JET SETS UP ON THE NORTHWEST SIDE OF THE STORM. TUE 18Z NAM/GFS ALSO SHOWING THIS LOW LEVEL JET INCREASE TO 70-80 KTS OVERNIGHT...BUT DIFFERING ON TIMING. EITHER WAY...WINDY AND TURBULENT CONDITIONS WILL PERSIST IN THE AREA THROUGH WEDNESDAY MORNING. DRY AIR WILL BEGIN TO ENTRAIN INTO THE STORM STARTING WEDNESDAY MORNING. RAIN WILL THEN TAPER OFF FROM WEST TO EAST THROUGH THE AFTERNOON. BULK OF THE RAIN SHOULD BE ALONG THE COAST WHILE THE WESTERN EDGE COULD REMAIN OVER EASTERN CWA (DAN-LYH) INTO WEDNESDAY EVENING. PREV DISCUSSION... /ISSUED 245 PM EST TUE NOV 21 2006/ SHORT TERM /TONIGHT INTO WEDNESDAY/... CLOSE UPPER LOW OVER NORTHERN FLORIDA MOVES NORTHEAST TO OFF THE GEORGIA COAST BY WEDNESDAY MORNING. CONSENSUS IS USING THE GFS TRACK WITH THIS SYSTEM...BUT SLIGHTLY SLOWER TIMING BASED ON THE STRENGTH OF THE KICKER SHORT WAVE THAT IS COMING ONTO THE COAST IN THE PACIFIC NORTHWEST. THE GFS KEEPS THE BEST JET SUPPORT AND LEFT EXIT REGION OF THE 300 MB JET JUST EAST OF THE FORECAST AREA TONIGHT BUT IS STILL SHOWING STRONG UPPER DIFFLUENCE UNTIL 12Z WEDNESDAY. VELOCITY AZIMUTH DISPLAYS FROM AREA RADARS ARE ALREADY SHOWING 50 KNOT 850 MB WINDS TO OUR SOUTHEAST AND WINDS ARE FORECAST TO BE IN THE 25 TO 55 KNOT RANGE FROM NORTHWEST TO SOUTHEAST ACROSS THE COUNTY WARNING AREA TONIGHT. THIS SHOULD HELP LOW LEVEL CONVERGENCE ALONG AND EAST OF THE MOUNTAINS BETWEEN 00-12Z WEDNESDAY. EXPECT THAT THIS GOOD MIXING AND THE CLOUD COVER WILL PREVENT TEMPERATURES FROM DROPPING BELOW FREEZING BEFORE THE RAIN STARTS. REST OF THE FORECAST TEMPERATURE PROFILE IS WELL ABOVE FREEZING WITH DECENT WARM AIR ADVECTION AT 850 MB. GRIDS WILL REFLECT A NON DIURNAL TEMPERATURE TREND TONIGHT...WITH VALUES DROPPING AFTER SUNSET BUT THEN RECOVERING OVERNIGHT WITH INCREASING DEW POINTS AND CLOUD COVER. NAM WAS MORE AGGRESSIVE AND FASTER WITH THE HIGHER RELATIVE HUMIDITY VALUES...BRINGING CLOUDS ALL THE WAY UP TO THE GREENBRIER VALLEY BY 03Z TONIGHT AND LOW LEVEL MOISTURE INTO THE SOUTHEAST COUNTIES BY 00Z. IN CONTRAST...THE GFS NEVER DOES BRING THE CLOUDS INTO THE NORTHWEST COUNTIES AND HOLDS THE DEEPEST LOW LEVEL MOISTURE AND FORCING TO THE SOUTH OF THE COUNTY WARNING AREA THROUGH 12Z WEDNESDAY. LOOKING AT CURRENT OBSERVATIONS SHOWS THE NORTHERN EDGE OF THE PRECIPITATION FROM HICKORY TO ROANOKE RAPIDS NORTH CAROLINA WITH SURFACE DEW POINTS OF AT LEAST 30 DEGREES IN THE AREA WHERE THE RAIN IS REACHING THE GROUND. SO LOW AND MID LEVEL CLOUDS NEED TO COME IN AND THERE IS STILL SOME SATURATION THAT NEEDS TO OCCUR BEFORE THERE WILL BE ANY PRECIPITATION IN THE COUNTY WARNING AREA. GFS HAS A BETTER HANDLE WITH THE RELATIVE HUMIDITY FORECAST COMPARED TO WHERE THE PRECIPITATION IS NOW AND IT BRINGS THE CHANCE INTO THE SOUTHEAST BY 06Z. WILL SLOW DOWN TIMING OF INCREASING THE SURFACE DEW POINTS AND CHANCE OF RAIN TO REFLECT THIS TREND. LONG TERM /WEDNESDAY THROUGH TUESDAY/... A MORE PROGRESSIVE SYSTEM IS EXPECTED WEDNESDAY INTO THURSDAY. AS THE LOW CENTER LIFTS NORTH ALONG THE COAST...MOST OF THE PRECIP WILL REMAIN ALONG THE COAST. ELECTED TO TRIM BACK THE WESTERN EXTENT OF CLOUDS AND RAIN WITH SYSTEM. DECIDED TO MENTION LIKELY POPS WEDNESDAY FOR SOUTHEAST PORTION OF FA WHICH MATCHES UP NICELY WITH RAH. TEMPERATURES ON WEDNESDAY AND THURSDAY ARE TRICKY BECAUSE OF CLOUD COVER...AND POTENTIAL WEDGE WITH RAIN. FELT THAT DRIER AIR WILL PUSH NORTHEAST ACROSS AREA ON THURSDAY NIGHT INTO FRIDAY. CUT CLOUD COVER AND WENT WITH LOWER DEW POINTS TEMPERATURES THURSDAY NIGHT INTO FRIDAY. FOR MEDIUM RANGE FOLLOWED HPCGUIDE WHICH WAS A BLEND OF THE GFS AND ECMWF. IN GENERAL...WENT FASTER WITH LIFTING OF COASTAL LOW OUT AND SLOWER WITH FRONTAL WAVES EARLY NEXT WEEK. AVIATION /20Z-18Z/... MVFR TO IFR CEILINGS WILL SPREAD INTO LYH AND DAN JUST AFTER 00Z. RAIN AND THE EASTERLY COMPONENT TO THE LOW LEVEL WINDS WILL KEEP CEILINGS LOW OVERNIGHT. STILL UNCERTAIN HOW FAR WEST THE LOWER CLOUDS WILL GET BUT PLAN TO HAVE A SHORT PERIOD OF MVFR CLOUDS AND RAIN AT ROA...BUT NOT AT BLF AND LWB. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ AVIATION...DS va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 1053 AM EST WED NOV 22 2006 .SHORT TERM /REST OF TODAY/... MORNING UPDATE WILL REFLECT ADJUSTMENTS TO THE TREND OF THE PROGRESSION OF DEFORMATION ZONE RAIN ASSOCIATED ON THE NORTHWEST SIDE OF THE MAIN UPPER LOW. LATEST MODEL GUIDANCE SUGGESTS A PROGRESSION OF THE BULK OF THE RAIN NO FARTHER WEST THEN ABOUT THE CREST OF THE BLUE RIDGE...WITH LIMITED PRECIPITATION WEST OF THAT AREA. WILL BE A VERY FINE LINE BETWEEN AREAS THAT DO RECEIVE RAIN AND THOSE THAT DO NOT. VERY LIMITED...IF ANY...PATCHES OF RAIN JUST WEST OF THE MAIN AREA OF RAIN ARE EXPECTED. BUT SINCE I AM NOT PREPARED TO HAVE A BINARY FORECAST WITH A CLEAR CUT LINE OF 100 PERCENT RAIN NEXT TO AN AREA WITH ZERO PERCENT RAIN...I WILL CONTINUE WITH A FAIRLY TIGHT GRADIENT OF PRECIPITATION CHANCES RANGING INTO THE LIKLEY AND CHANCE CATEGORIES. BUT I WILL SHIFT THE CENTER OF THIS GRADIENT EASTWARD AS COMPARED TO THE EARLIER POSITION. NOW THE EDGE OF THE LIKELY POPS WILL BE NEAR THE CREST OF THE BLUE RIDGE...WITH THE CHANCE CATEGORY FOLLOWING CLOSE TO THE I-81 CORRIDOR. EVEN THE NEWEST GUIDANCE HAS DROPPED THE BALL BY NOT INITIALIZING DEW POINTS IN THE TEENS ACROSS PORTIONS OF THE NEW RIVER VALLEY WHERE THEY ARE CURRENTLY BEING EXPERIENCED. HAD WONDERING IF WHEN RAIN ARRIVES WE WOULD SEE A GENEROUS DROP IN TEMPERATURE TOWARDS THE WET BULB TEMPERATURE AND AS SUCH HAVE A BRIEF PERIOD OF A MIX OF WINTRY PRECIP. HOWEVER...IN ANALYZING THE 12Z KFCX SOUNDING THERE IS ONLY A VERY NARROW LAYER OF AIR WITH WET BULB TEMPERATURES RIGHT AT 0 C WITH THE REST OF THE SOUNDING HAVING BOTH TEMPERATURES AND WET BULB TEMPS ABOVE FREEZING. THIS WITH ONLY MINIMAL PRECIPITATION EXPECTED TO REACH THIS AREA...DO NOT EXPECT ANY WINTRY CONCERNS AND WILL KEEP PRECIPITATION RAIN ONLY. OTHER ADJUSTMENTS HAVE BEEN TO WARM HIGH TEMPERATURES IN THE WEST A BIT. CLOUD COVER THERE SHOULD REMAIN ON THE THIN SIDE HELPING TEMPERATURES TO INCREASE MORE THAN ELSEWHERE ACROSS THE REGION...AND ALSO HAVE WARMED TEMPERATURES IN THE NORTH CAROLINA FOOTHILLS WHERE CURRENT CONDITIONS WERE ALREADY MILDER THAN THE PREVIOUSLY EXPECTED HIGH TEMPS. && .PREV DISCUSSION... /ISSUED 635 AM EST WED NOV 22 2006/ AVIATION /11Z-06Z/... RAIN HAS MOSTLY MOVED OUT OF THE SERVICE AREA FOR THE TIME BEING...HOWEVER LOOK FOR A RE-DEVELOPMENT OF THE RAIN AND A LOWERING OF CIGS DURING THE DAY FROM ROA EAST. PREVAILING CONDITIONS SHUD REMAIN AT MVFR OR BETTER THRU THE NEXT 24 HOURS. STRONG NE WINDS ALOFT WILL CREATE LLWS CONDITIONS AT BLF AND LWB WHERE SFC WINDS ARE LIGHT. AT ROA/LYH/DAN LLWS WILL BE LESS OF PROBLEM DUE TO STRONGER WINDS AT THE SFC...BUT STILL EXPECT 40-60 KT WINDS FROM 2K FT AND UP. PREV DISCUSSION... /ISSUED 258 AM EST WED NOV 22 2006/ SHORT TERM /TODAY THROUGH FRIDAY/... CLOSED UPR LOW CRNTLY OFF THE GEORGIA COAST STATIONARY OVER THE PAST FEW HOURS. RAINFALL SPREADING WEST TO THE MTNS DURING THE EVENING HOURS IS STARTING TO DIMINISH ON THE NORTHWEST END AS DRY AIR GETS PULLED INTO THE SYSTEM FROM THE NORTHEAST. WETBULB TEMPS ARE BELOW FRZG IN THE WEST THIS MORNING WHICH COULD RESULT IN FRZG RAIN...HOWEVER BELIEVE AT THIS POINT THAT ANY PCPN WILL BE TOO LIGHT TO PUSH TEMPS DOWN THAT LOW...ESP BASED ON CRNT RADAR TRENDS. RAINFALL RATES EARLIER IN THE EVENING WERE A LITTLE WORRISOME DOWN ALONG THE NC/VA LINE HOWEVER THOSE RATES HAVE LIGHTENED UP QUITE A BIT SINCE THEN...TO ARND 0.10 INCH PER HOUR...SO THINK FLOODING THREAT WILL REMAIN SUPPRESSED TO OUR SOUTH. NE SFC WINDS ARE GUSTING TO 25-30 KTS AT TIMES. THIS MAY INCREASE SOMEWHAT DURING THE DAY AS GRADIENT TIGHTENS...BUT SHUD REMAIN WELL BELOW ADV CRITERIA FOR OUR AREA. AS THE UPR LOW MOVES NORTH LATER TODAY AND TNGT ANOTHER SURGE OF RAIN WILL LIKELY WRAP ARND THE NORTH END OF THE LOW AND SPREAD WEST ACROSS MUCH OF THE FCST AREA BEFORE THE SYSTEM PULLS OUT. MODELS NOW IN MUCH BETTER AGREEMENT IN PULLING THE SYSTEM OUT OF SW VA BY THURSDAY AFTERNOON. AFTERWHICH MILD HIGH PRESSURE MOVES OVER THE SOUTHERN APPS/MID-ATLANTIC REGION TO PRODUCE A VERY TRANQUIL WEEKEND. PREV DISCUSSION... /ISSUED 1247 AM EST WED NOV 22 2006/ AVIATION /06Z-06Z/... STRONG UPPER LOW OVER THE SOUTHEAST COAST OF THE U.S. WILL SEND RAIN TO MOST AREAS MAINLY EAST OF THE BLUE RIDGE THIS PERIOD. CIGS WILL DROP TO MVFR ACROSS THE BLUE RIDGE BY 08Z...WITH MVFR CONDITIONS PREVAILING FURTHER EAST AT KLYH AND KDAN THROUGH MIDDAY...AND EVEN LONGER AT DANVILLE. APPEARS LYH MAY BREAK OUT FOR A LIMITED TIME DURING THE EARLY AFTN. FURTHER WEST INTO SE WV...THE RAIN SHOULD HOLD OFF...AS THE SYSTEM WILL BE WOUND UP TIGHTLY KEEPING A SHARP GRADIENT IN PRECIP SHIELD. LEWISBURG SHOULD REMAIN VFR THIS PERIOD...BUT AS THE UPPER LOW STARTS MOVING NORTH TO THE OUTER BANKS...A LOWER MVFR CLD SHIELD SHOULD MOVE INTO LWB AROUND 03Z. PREV DISCUSSION... /ISSUED 935 PM EST TUE NOV 21 2006/ UPDATE... BASICALLY FOLLOWED TREND OF EARLIER UPDATE WITH HIGHER POPS AND WINDS GRIDS IN THE SOUTHEAST. FOLLOWED WRF-RUC PCPN FCST WITH HIGHEST QPF NEARING 1 INCH OVER THE OVER THE SE BY 18Z. 02Z RAINFALL AMOUNTS HAVE REACHED 0.48" AT CASWELL RAWS AND 0.37" AT DANVILLE ASOS. MID SHIFT WILL HAVE TO KEEP CLOSE EYE ON PCPN TRENDS AS RAH HAS PUSHED FLASH FLOOD WATCH TO OUR SE BORDER. RAISED OVERNIGHT MINS AS CLOUDS/WIND WILL OFFSET ANY DYNAMIC COOLING FROM ANY PCPN. PREV DISCUSSION... /ISSUED 715 PM EST TUE NOV 21 2006/ UPDATE... RAISED RAIN POPS IN THE EAST IN RESPONSE TO CURRENT RADAR TRENDS. INSERTED CHC OR SLIGHT CHC OF ZR OR IP IN THE WESTERN VALLEYS AS BUFKIT SOUNDINGS SHOW MIXED PRECIP PSBL AND DYNAMIC COOLING MAY BE A FACTOR AS TDS REMAIN VERY LOW. HOPEFULLY STRONG ENE FLOW WILL SCOUR OUT ANY TRAPPED VALLEY AIR AND ONSET OF CLOUDS AROUND SUNSET SHOULD LESSEN TRAPPED COLD AIR ISSUE. PREV DISCUSSION... /ISSUED 649 PM EST TUE NOV 21 2006/ AVIATION /00Z-24Z/... CUT-OFF LOW OFF THE SE COAST WILL REMAIN NEARLY STATIONARY THROUGH THE PERIOD. WITH ABUNDANT DRY AIR IN PLACE...RAIN SHIELD TRYING TO MOVE TO THE WEST BUT RAIN ONLY REACHING THE GROUND IN SOUTHSIDE VA (23Z TUE). SHORT WAVES ROTATING AROUND THIS LOW WILL BRING PERIODS OF RAIN TO AREAS EAST OF THE BLUE RIDGE OVERNIGHT...PARTICULARLY THE PIEDMONT REGION OF SOUTHSIDE VA AND NORTHWESTERN NC. RAIN BANDS COULD BECOME INTENSE WHICH IN TURN WILL LOWER VISIBILITIES AS 55-65 KT LOW LEVEL JET SETS UP ON THE NORTHWEST SIDE OF THE STORM. TUE 18Z NAM/GFS ALSO SHOWING THIS LOW LEVEL JET INCREASE TO 70-80 KTS OVERNIGHT...BUT DIFFERING ON TIMING. EITHER WAY...WINDY AND TURBULENT CONDITIONS WILL PERSIST IN THE AREA THROUGH WEDNESDAY MORNING. DRY AIR WILL BEGIN TO ENTRAIN INTO THE STORM STARTING WEDNESDAY MORNING. RAIN WILL THEN TAPER OFF FROM WEST TO EAST THROUGH THE AFTERNOON. BULK OF THE RAIN SHOULD BE ALONG THE COAST WHILE THE WESTERN EDGE COULD REMAIN OVER EASTERN CWA (DAN-LYH) INTO WEDNESDAY EVENING. PREV DISCUSSION... /ISSUED 245 PM EST TUE NOV 21 2006/ SHORT TERM /TONIGHT INTO WEDNESDAY/... CLOSE UPPER LOW OVER NORTHERN FLORIDA MOVES NORTHEAST TO OFF THE GEORGIA COAST BY WEDNESDAY MORNING. CONSENSUS IS USING THE GFS TRACK WITH THIS SYSTEM...BUT SLIGHTLY SLOWER TIMING BASED ON THE STRENGTH OF THE KICKER SHORT WAVE THAT IS COMING ONTO THE COAST IN THE PACIFIC NORTHWEST. THE GFS KEEPS THE BEST JET SUPPORT AND LEFT EXIT REGION OF THE 300 MB JET JUST EAST OF THE FORECAST AREA TONIGHT BUT IS STILL SHOWING STRONG UPPER DIFFLUENCE UNTIL 12Z WEDNESDAY. VELOCITY AZIMUTH DISPLAYS FROM AREA RADARS ARE ALREADY SHOWING 50 KNOT 850 MB WINDS TO OUR SOUTHEAST AND WINDS ARE FORECAST TO BE IN THE 25 TO 55 KNOT RANGE FROM NORTHWEST TO SOUTHEAST ACROSS THE COUNTY WARNING AREA TONIGHT. THIS SHOULD HELP LOW LEVEL CONVERGENCE ALONG AND EAST OF THE MOUNTAINS BETWEEN 00-12Z WEDNESDAY. EXPECT THAT THIS GOOD MIXING AND THE CLOUD COVER WILL PREVENT TEMPERATURES FROM DROPPING BELOW FREEZING BEFORE THE RAIN STARTS. REST OF THE FORECAST TEMPERATURE PROFILE IS WELL ABOVE FREEZING WITH DECENT WARM AIR ADVECTION AT 850 MB. GRIDS WILL REFLECT A NON DIURNAL TEMPERATURE TREND TONIGHT...WITH VALUES DROPPING AFTER SUNSET BUT THEN RECOVERING OVERNIGHT WITH INCREASING DEW POINTS AND CLOUD COVER. NAM WAS MORE AGGRESSIVE AND FASTER WITH THE HIGHER RELATIVE HUMIDITY VALUES...BRINGING CLOUDS ALL THE WAY UP TO THE GREENBRIER VALLEY BY 03Z TONIGHT AND LOW LEVEL MOISTURE INTO THE SOUTHEAST COUNTIES BY 00Z. IN CONTRAST...THE GFS NEVER DOES BRING THE CLOUDS INTO THE NORTHWEST COUNTIES AND HOLDS THE DEEPEST LOW LEVEL MOISTURE AND FORCING TO THE SOUTH OF THE COUNTY WARNING AREA THROUGH 12Z WEDNESDAY. LOOKING AT CURRENT OBSERVATIONS SHOWS THE NORTHERN EDGE OF THE PRECIPITATION FROM HICKORY TO ROANOKE RAPIDS NORTH CAROLINA WITH SURFACE DEW POINTS OF AT LEAST 30 DEGREES IN THE AREA WHERE THE RAIN IS REACHING THE GROUND. SO LOW AND MID LEVEL CLOUDS NEED TO COME IN AND THERE IS STILL SOME SATURATION THAT NEEDS TO OCCUR BEFORE THERE WILL BE ANY PRECIPITATION IN THE COUNTY WARNING AREA. GFS HAS A BETTER HANDLE WITH THE RELATIVE HUMIDITY FORECAST COMPARED TO WHERE THE PRECIPITATION IS NOW AND IT BRINGS THE CHANCE INTO THE SOUTHEAST BY 06Z. WILL SLOW DOWN TIMING OF INCREASING THE SURFACE DEW POINTS AND CHANCE OF RAIN TO REFLECT THIS TREND. LONG TERM /WEDNESDAY THROUGH TUESDAY/... A MORE PROGRESSIVE SYSTEM IS EXPECTED WEDNESDAY INTO THURSDAY. AS THE LOW CENTER LIFTS NORTH ALONG THE COAST...MOST OF THE PRECIP WILL REMAIN ALONG THE COAST. ELECTED TO TRIM BACK THE WESTERN EXTENT OF CLOUDS AND RAIN WITH SYSTEM. DECIDED TO MENTION LIKELY POPS WEDNESDAY FOR SOUTHEAST PORTION OF FA WHICH MATCHES UP NICELY WITH RAH. TEMPERATURES ON WEDNESDAY AND THURSDAY ARE TRICKY BECAUSE OF CLOUD COVER...AND POTENTIAL WEDGE WITH RAIN. FELT THAT DRIER AIR WILL PUSH NORTHEAST ACROSS AREA ON THURSDAY NIGHT INTO FRIDAY. CUT CLOUD COVER AND WENT WITH LOWER DEW POINTS TEMPERATURES THURSDAY NIGHT INTO FRIDAY. FOR MEDIUM RANGE FOLLOWED HPCGUIDE WHICH WAS A BLEND OF THE GFS AND ECMWF. IN GENERAL...WENT FASTER WITH LIFTING OF COASTAL LOW OUT AND SLOWER WITH FRONTAL WAVES EARLY NEXT WEEK. AVIATION /20Z-18Z/... MVFR TO IFR CEILINGS WILL SPREAD INTO LYH AND DAN JUST AFTER 00Z. RAIN AND THE EASTERLY COMPONENT TO THE LOW LEVEL WINDS WILL KEEP CEILINGS LOW OVERNIGHT. STILL UNCERTAIN HOW FAR WEST THE LOWER CLOUDS WILL GET BUT PLAN TO HAVE A SHORT PERIOD OF MVFR CLOUDS AND RAIN AT ROA...BUT NOT AT BLF AND LWB. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SHORT TERM...DS va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 635 AM EST WED NOV 22 2006 .AVIATION /11Z-06Z/... RAIN HAS MOSTLY MOVED OUT OF THE SERVICE AREA FOR THE TIME BEING...HOWEVER LOOK FOR A RE-DEVELOPMENT OF THE RAIN AND A LOWERING OF CIGS DURING THE DAY FROM ROA EAST. PREVAILING CONDITIONS SHUD REMAIN AT MVFR OR BETTER THRU THE NEXT 24 HOURS. STRONG NE WINDS ALOFT WILL CREATE LLWS CONDITIONS AT BLF AND LWB WHERE SFC WINDS ARE LIGHT. AT ROA/LYH/DAN LLWS WILL BE LESS OF PROBLEM DUE TO STRONGER WINDS AT THE SFC...BUT STILL EXPECT 40-60 KT WINDS FROM 2K FT AND UP. && .PREV DISCUSSION... /ISSUED 258 AM EST WED NOV 22 2006/ SHORT TERM /TODAY THROUGH FRIDAY/... CLOSED UPR LOW CRNTLY OFF THE GEORGIA COAST STATIONARY OVER THE PAST FEW HOURS. RAINFALL SPREADING WEST TO THE MTNS DURING THE EVENING HOURS IS STARTING TO DIMINISH ON THE NORTHWEST END AS DRY AIR GETS PULLED INTO THE SYSTEM FROM THE NORTHEAST. WETBULB TEMPS ARE BELOW FRZG IN THE WEST THIS MORNING WHICH COULD RESULT IN FRZG RAIN...HOWEVER BELIEVE AT THIS POINT THAT ANY PCPN WILL BE TOO LIGHT TO PUSH TEMPS DOWN THAT LOW...ESP BASED ON CRNT RADAR TRENDS. RAINFALL RATES EARLIER IN THE EVENING WERE A LITTLE WORRISOME DOWN ALONG THE NC/VA LINE HOWEVER THOSE RATES HAVE LIGHTENED UP QUITE A BIT SINCE THEN...TO ARND 0.10 INCH PER HOUR...SO THINK FLOODING THREAT WILL REMAIN SUPPRESSED TO OUR SOUTH. NE SFC WINDS ARE GUSTING TO 25-30 KTS AT TIMES. THIS MAY INCREASE SOMEWHAT DURING THE DAY AS GRADIENT TIGHTENS...BUT SHUD REMAIN WELL BELOW ADV CRITERIA FOR OUR AREA. AS THE UPR LOW MOVES NORTH LATER TODAY AND TNGT ANOTHER SURGE OF RAIN WILL LIKELY WRAP ARND THE NORTH END OF THE LOW AND SPREAD WEST ACROSS MUCH OF THE FCST AREA BEFORE THE SYSTEM PULLS OUT. MODELS NOW IN MUCH BETTER AGREEMENT IN PULLING THE SYSTEM OUT OF SW VA BY THURSDAY AFTERNOON. AFTERWHICH MILD HIGH PRESSURE MOVES OVER THE SOUTHERN APPS/MID-ATLANTIC REGION TO PRODUCE A VERY TRANQUIL WEEKEND. PREV DISCUSSION... /ISSUED 1247 AM EST WED NOV 22 2006/ AVIATION /06Z-06Z/... STRONG UPPER LOW OVER THE SOUTHEAST COAST OF THE U.S. WILL SEND RAIN TO MOST AREAS MAINLY EAST OF THE BLUE RIDGE THIS PERIOD. CIGS WILL DROP TO MVFR ACROSS THE BLUE RIDGE BY 08Z...WITH MVFR CONDITIONS PREVAILING FURTHER EAST AT KLYH AND KDAN THROUGH MIDDAY...AND EVEN LONGER AT DANVILLE. APPEARS LYH MAY BREAK OUT FOR A LIMITED TIME DURING THE EARLY AFTN. FURTHER WEST INTO SE WV...THE RAIN SHOULD HOLD OFF...AS THE SYSTEM WILL BE WOUND UP TIGHTLY KEEPING A SHARP GRADIENT IN PRECIP SHIELD. LEWISBURG SHOULD REMAIN VFR THIS PERIOD...BUT AS THE UPPER LOW STARTS MOVING NORTH TO THE OUTER BANKS...A LOWER MVFR CLD SHIELD SHOULD MOVE INTO LWB AROUND 03Z. PREV DISCUSSION... /ISSUED 935 PM EST TUE NOV 21 2006/ UPDATE... BASICALLY FOLLOWED TREND OF EARLIER UPDATE WITH HIGHER POPS AND WINDS GRIDS IN THE SOUTHEAST. FOLLOWED WRF-RUC PCPN FCST WITH HIGHEST QPF NEARING 1 INCH OVER THE OVER THE SE BY 18Z. 02Z RAINFALL AMOUNTS HAVE REACHED 0.48" AT CASWELL RAWS AND 0.37" AT DANVILLE ASOS. MID SHIFT WILL HAVE TO KEEP CLOSE EYE ON PCPN TRENDS AS RAH HAS PUSHED FLASH FLOOD WATCH TO OUR SE BORDER. RAISED OVERNIGHT MINS AS CLOUDS/WIND WILL OFFSET ANY DYNAMIC COOLING FROM ANY PCPN. PREV DISCUSSION... /ISSUED 715 PM EST TUE NOV 21 2006/ UPDATE... RAISED RAIN POPS IN THE EAST IN RESPONSE TO CURRENT RADAR TRENDS. INSERTED CHC OR SLIGHT CHC OF ZR OR IP IN THE WESTERN VALLEYS AS BUFKIT SOUNDINGS SHOW MIXED PRECIP PSBL AND DYNAMIC COOLING MAY BE A FACTOR AS TDS REMAIN VERY LOW. HOPEFULLY STRONG ENE FLOW WILL SCOUR OUT ANY TRAPPED VALLEY AIR AND ONSET OF CLOUDS AROUND SUNSET SHOULD LESSEN TRAPPED COLD AIR ISSUE. PREV DISCUSSION... /ISSUED 649 PM EST TUE NOV 21 2006/ AVIATION /00Z-24Z/... CUT-OFF LOW OFF THE SE COAST WILL REMAIN NEARLY STATIONARY THROUGH THE PERIOD. WITH ABUNDANT DRY AIR IN PLACE...RAIN SHIELD TRYING TO MOVE TO THE WEST BUT RAIN ONLY REACHING THE GROUND IN SOUTHSIDE VA (23Z TUE). SHORT WAVES ROTATING AROUND THIS LOW WILL BRING PERIODS OF RAIN TO AREAS EAST OF THE BLUE RIDGE OVERNIGHT...PARTICULARLY THE PIEDMONT REGION OF SOUTHSIDE VA AND NORTHWESTERN NC. RAIN BANDS COULD BECOME INTENSE WHICH IN TURN WILL LOWER VISIBILITIES AS 55-65 KT LOW LEVEL JET SETS UP ON THE NORTHWEST SIDE OF THE STORM. TUE 18Z NAM/GFS ALSO SHOWING THIS LOW LEVEL JET INCREASE TO 70-80 KTS OVERNIGHT...BUT DIFFERING ON TIMING. EITHER WAY...WINDY AND TURBULENT CONDITIONS WILL PERSIST IN THE AREA THROUGH WEDNESDAY MORNING. DRY AIR WILL BEGIN TO ENTRAIN INTO THE STORM STARTING WEDNESDAY MORNING. RAIN WILL THEN TAPER OFF FROM WEST TO EAST THROUGH THE AFTERNOON. BULK OF THE RAIN SHOULD BE ALONG THE COAST WHILE THE WESTERN EDGE COULD REMAIN OVER EASTERN CWA (DAN-LYH) INTO WEDNESDAY EVENING. PREV DISCUSSION... /ISSUED 245 PM EST TUE NOV 21 2006/ SHORT TERM /TONIGHT INTO WEDNESDAY/... CLOSE UPPER LOW OVER NORTHERN FLORIDA MOVES NORTHEAST TO OFF THE GEORGIA COAST BY WEDNESDAY MORNING. CONSENSUS IS USING THE GFS TRACK WITH THIS SYSTEM...BUT SLIGHTLY SLOWER TIMING BASED ON THE STRENGTH OF THE KICKER SHORT WAVE THAT IS COMING ONTO THE COAST IN THE PACIFIC NORTHWEST. THE GFS KEEPS THE BEST JET SUPPORT AND LEFT EXIT REGION OF THE 300 MB JET JUST EAST OF THE FORECAST AREA TONIGHT BUT IS STILL SHOWING STRONG UPPER DIFFLUENCE UNTIL 12Z WEDNESDAY. VELOCITY AZIMUTH DISPLAYS FROM AREA RADARS ARE ALREADY SHOWING 50 KNOT 850 MB WINDS TO OUR SOUTHEAST AND WINDS ARE FORECAST TO BE IN THE 25 TO 55 KNOT RANGE FROM NORTHWEST TO SOUTHEAST ACROSS THE COUNTY WARNING AREA TONIGHT. THIS SHOULD HELP LOW LEVEL CONVERGENCE ALONG AND EAST OF THE MOUNTAINS BETWEEN 00-12Z WEDNESDAY. EXPECT THAT THIS GOOD MIXING AND THE CLOUD COVER WILL PREVENT TEMPERATURES FROM DROPPING BELOW FREEZING BEFORE THE RAIN STARTS. REST OF THE FORECAST TEMPERATURE PROFILE IS WELL ABOVE FREEZING WITH DECENT WARM AIR ADVECTION AT 850 MB. GRIDS WILL REFLECT A NON DIURNAL TEMPERATURE TREND TONIGHT...WITH VALUES DROPPING AFTER SUNSET BUT THEN RECOVERING OVERNIGHT WITH INCREASING DEW POINTS AND CLOUD COVER. NAM WAS MORE AGGRESSIVE AND FASTER WITH THE HIGHER RELATIVE HUMIDITY VALUES...BRINGING CLOUDS ALL THE WAY UP TO THE GREENBRIER VALLEY BY 03Z TONIGHT AND LOW LEVEL MOISTURE INTO THE SOUTHEAST COUNTIES BY 00Z. IN CONTRAST...THE GFS NEVER DOES BRING THE CLOUDS INTO THE NORTHWEST COUNTIES AND HOLDS THE DEEPEST LOW LEVEL MOISTURE AND FORCING TO THE SOUTH OF THE COUNTY WARNING AREA THROUGH 12Z WEDNESDAY. LOOKING AT CURRENT OBSERVATIONS SHOWS THE NORTHERN EDGE OF THE PRECIPITATION FROM HICKORY TO ROANOKE RAPIDS NORTH CAROLINA WITH SURFACE DEW POINTS OF AT LEAST 30 DEGREES IN THE AREA WHERE THE RAIN IS REACHING THE GROUND. SO LOW AND MID LEVEL CLOUDS NEED TO COME IN AND THERE IS STILL SOME SATURATION THAT NEEDS TO OCCUR BEFORE THERE WILL BE ANY PRECIPITATION IN THE COUNTY WARNING AREA. GFS HAS A BETTER HANDLE WITH THE RELATIVE HUMIDITY FORECAST COMPARED TO WHERE THE PRECIPITATION IS NOW AND IT BRINGS THE CHANCE INTO THE SOUTHEAST BY 06Z. WILL SLOW DOWN TIMING OF INCREASING THE SURFACE DEW POINTS AND CHANCE OF RAIN TO REFLECT THIS TREND. LONG TERM /WEDNESDAY THROUGH TUESDAY/... A MORE PROGRESSIVE SYSTEM IS EXPECTED WEDNESDAY INTO THURSDAY. AS THE LOW CENTER LIFTS NORTH ALONG THE COAST...MOST OF THE PRECIP WILL REMAIN ALONG THE COAST. ELECTED TO TRIM BACK THE WESTERN EXTENT OF CLOUDS AND RAIN WITH SYSTEM. DECIDED TO MENTION LIKELY POPS WEDNESDAY FOR SOUTHEAST PORTION OF FA WHICH MATCHES UP NICELY WITH RAH. TEMPERATURES ON WEDNESDAY AND THURSDAY ARE TRICKY BECAUSE OF CLOUD COVER...AND POTENTIAL WEDGE WITH RAIN. FELT THAT DRIER AIR WILL PUSH NORTHEAST ACROSS AREA ON THURSDAY NIGHT INTO FRIDAY. CUT CLOUD COVER AND WENT WITH LOWER DEW POINTS TEMPERATURES THURSDAY NIGHT INTO FRIDAY. FOR MEDIUM RANGE FOLLOWED HPCGUIDE WHICH WAS A BLEND OF THE GFS AND ECMWF. IN GENERAL...WENT FASTER WITH LIFTING OF COASTAL LOW OUT AND SLOWER WITH FRONTAL WAVES EARLY NEXT WEEK. AVIATION /20Z-18Z/... MVFR TO IFR CEILINGS WILL SPREAD INTO LYH AND DAN JUST AFTER 00Z. RAIN AND THE EASTERLY COMPONENT TO THE LOW LEVEL WINDS WILL KEEP CEILINGS LOW OVERNIGHT. STILL UNCERTAIN HOW FAR WEST THE LOWER CLOUDS WILL GET BUT PLAN TO HAVE A SHORT PERIOD OF MVFR CLOUDS AND RAIN AT ROA...BUT NOT AT BLF AND LWB. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ AVIATION...JS va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 344 AM EST THU NOV 23 2006 .DISCUSSION... DRY/WARM WEATHER FOR LATE NOV WILL CONTINUE FOR THE NEXT COUPLE OF DAYS...PROVIDING NO PROBLEMS FOR HOLIDAY TRAVEL ACROSS UPPER MI. PCPN CONCERNS ARE MINIMAL OR NONEXISTENT INTO THE FIRST HALF OF THE WEEKEND...SO TEMPS WILL BE THE MAIN FCST ISSUE. WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROFFING ALONG THE W COAST OF NAMERICA WITH PERSISTENT WSW FLOW/RIDGING AND ABOVE NORMAL HEIGHTS DOWNSTREAM ACROSS THE CNTRL CONUS INTO SE CANADA. A POTENT LOOKING SHORTWAVE WAS TRACKING ENE THRU NRN ONTARIO TO JAMES BAY. PCPN ASSOCIATED WITH SHORTWAVE PASSED WELL N OF UPPER MI AS AIRMASS HAS REMAINED TOO DRY TO SUPPORT EVEN CLOUDS HERE...EVEN ALONG ASSOCIATED COLD FRONT WHICH IS APPROACHING WRN UPPER MI. DRY AIRMASS IS SHOWN NICELY BY THE 00Z KINL/KGRB SOUNDINGS. SHORTWAVE HAS TRACKED ALONG SHARP BAROCLINIC ZONE OVER SCNTRL CANADA. AT THE SFC...TEMPS REVEAL BITTER LATE FALL ARCTIC AIR SPREADING S ACROSS SASKATCHEWAN AND MANITOBA BEHIND SHORTWAVE. READINGS AS OF 08Z WERE AS LOW AS -33F IN NRN SASKATCHEWAN WITH TEENS AND 20S BELOW COMMON. AS CLOSE AS THE N END OF LAKE WINNIPEG...TEMPS HAVE FALLEN TO AROUND 0F. THIS BUILDING ARCTIC AIR NOT TOO FAR TO THE NW IN CANADA LOOKS LIKE IT WILL PLUNGE FIRMLY INTO THE GREAT LAKES DURING THE LAST HALF OF NEXT WEEK. WELL TO THE W...NEXT SHORTWAVE OF INTEREST IS PUSHING ONSHORE OVER THE PACIFIC NW AND LOOKS VERY IMPRESSIVE. ALTHOUGH SHORTWAVE CONTINUES TO LIFT ENE WELL TO THE N OF UPPER MI...ASSOCIATED COLD FRONT SHOULD HAVE LITTLE TROUBLE PASSING S OF THE FCST AREA THIS MORNING AS NICE AREA OF PRES RISES (CURRENTLY UPWARDS OF 8MB/3HR TO THE NW IN ONTARIO) ASSIST FRONTAL MOVEMENT. DURING THE DAY...SFC HIGH PRES BUILDING INTO NRN ONTARIO WILL ENSURE THE DEVELOPMENT OF A NE TO E SFC WIND. THIS WILL CERTAINLY HAVE AN IMPACT ON TEMPS. WITH EARLY FROPA ACROSS THE N...HIGH TEMPS SHOULD BE HELD TO THE MID/UPPER 40S PER GOING FCST WITH EXPECTATION OF LITTLE TEMP RISE ONCE WINDS SHIFT OFF THE LAKE. ACROSS THE S AND ESPECIALLY THE INTERIOR SW...MIXING TO 925MB ON NAM/GFS FCST SOUNDINGS YIELDS MAX TEMPS IN THE MID OR EVEN UPPER 50S. MIXING HEIGHT IS CRITICAL THOUGH AND SHALLOW COOL AIR MOVING INTO THE AREA MAY LIMIT MIXING. HAVE THUS MAINTAINED GOING FCST OF HIGHS MAINLY IN THE LWR 50S THERE. SATELLITE IMAGERY SUGGEST NOTHING MORE THAN CI CLOUDS TODAY. WITH SFC HIGH TO THE NE IN ONTARIO THIS AFTN AND PRES FALLS ACROSS THE NRN PLAINS AHEAD OF PACIFIC NW SHORTWAVE WHICH WILL BE MOVING ACROSS THE NRN ROCKIES...NE WINDS WILL RAMP UP INTO THE 15-25KT RANGE ACROSS WRN LAKE SUPERIOR LATE AFTN INTO THE EVENING. SHORTWAVE WILL LIFT ENE ACROSS THE DAKOTAS/SRN MANITOBA TONIGHT. IN RESPONSE...LOW-LEVEL JET ACROSS THE NRN PLAINS THIS EVENING WILL SHIFT E TO THE UPPER LAKES BY 12Z FRI. THIS WILL RESULT IN MDT/STRONG ISENTROPIC ASCENT AS VIEWED ON THE 300K SFC (AROUND 700MB) WITH WINDS OF 40-50KT DIRECTED NEARLY PERPENDICULAR TO ISOBARS. HOWEVER...DUE TO LACK OF GOOD MOISTURE INFLOW...LOWEST CONDENSATION PRES DEFICITS REMAIN N OF UPPER MI AND WOULD THUS EXPECT PCPN TO ALSO OCCUR N OF HERE. AS WOULD BE EXPECTED...THIS DRY SCENARIO IS SUPPORTED BY FCST SOUNDINGS WHICH MAINTAIN SUFFICIENTLY DRY PROFILES TO SUGGEST LITTLE OR NO THREAT OF PCPN. WILL PROBABLY SEE AN INCREASE IN MID CLOUDS THOUGH...ESPECIALLY ACROSS THE N. INCREASING WINDS WILL LIMIT TEMP FALL TONIGHT...ESPECIALLY ACROSS THE W AND N. GOING FCST HAS THIS HANDLED WELL WITH MINS IN THE MID/UPPER 30S THERE. THERE WILL BE AN OPPORTUNITY TO COOL THIS EVENING OVER THE INTERIOR SCNTRL AND E BEFORE WINDS INCREASE WHICH SHOULD ALLOW TEMPS TO FALL TO THE LWR 30S. SHORTWAVE WILL LIFT THRU NRN ONTARIO TOWARD JAMES BAY FRI WITH ASSOCIATED COLD FRONT SWEEPING ACROSS FCST AREA. GFS/NAM ARE IN GOOD AGREEMENT TIMING FRONT TO THE WRN U.P. LATE MORNING AND EXITING THE E LATE AFTN/EARLY EVENING. WITH STRONG DEEP LAYER FORCING PASSING ACROSS ONTARIO AND MUCH WEAKER FORCING ALONG COLD FRONT AS IT CROSSES UPPER MI...FROPA SHOULD BE DRY ACROSS FCST AREA (HAVE KEPT SLIGHT CHC POPS THOUGH ACROSS WRN/NRN LAKE SUPERIOR CLOSER TO BETTER FORCING). A BAND OF STRATOCU WILL LIKELY ACCOMPANY FRONT WITH NAM/GFS BOTH SHOWING A RIBBON OF HIGH RH AT AND BLO 850MB. GOING FCST TEMPS IN THE MID/UPPER 40S LOOK FINE. WEAK PACIFIC HIGH PRES WILL SLIDE INTO THE WRN GREAT LAKES REGION FRI NIGHT AND EARLY SAT...ACCOMPANIED BY A DEEP DRY AIRMASS. SO MOSTLY CLEAR SKIES ARE EXPECTED. HAVE ACCORDINGLY DROPPED MINS BLO GUIDANCE FRI NIGHT DUE TO GOOD RADIATIONAL COOLING CONDITIONS. SHOULD SEE TEMPS DIP TO 20F IN THE TYPICAL COLD SPOTS. GFS/NAM/UKMET/CANADIAN SHOW A WEAK TROF SLIPPING E INTO WRN UPPER MI SAT AFTN. A VERY DRY DRY AIRMASS REMAINS...SO NOT EXPECTING ANY PCPN. SOME INCREASE IN MID/HIGH CLOUDS WILL OCCUR IN THE AFTN AS WAA PATTERN BEGINS TO DEVELOP UPSTREAM TO THE SW. FCST BECOMES A BIT MORE UNCERTAIN SUN AS SW FLOW/WAA AND WEAK SHORTWAVE CONSPIRE TO BRING A POTENTIAL PCPN EPISODE. HOWEVER... GFS/CANADIAN/ECMWF ARE IN GOOD AGREEMENT THAT THE WAA REGIME AND POSSIBLE WEAK SFC LOW SHOULD RESULT IN SOME PCPN WHICH WILL LIKELY BE RAIN BASED ON GFS FCST SOUNDINGS AND ECMWF 850MB TEMPS. BUMPED UP POPS INTO THE LOW CHC CATEGORY FOR SUN...BUT THAT WILL PROBABLY NEED TO BE INCREASED FURTHER IN LATER FCSTS. THERE MAY BE SOME LIGHT LES/FLURRIES BEHIND SYSTEM SUN NIGHT/MON MORNING OVER THE W BASED ON 00Z ECWMF. OTHERWISE...CONDITIONS WILL DRY OUT SUN NIGHT/MON AS SFC HIGH PRES RIDGE NOSES INTO THE UPPER LAKES. STRONG INDICATIONS PERSIST FROM ALL THE MEDIUM RANGE MODELS THAT A LONGWAVE TROF WILL PROGRESS E ACROSS THE CONUS NEXT WEEK WITH A POTENTIALLY STRONG SFC LOW AND SIGNIFICANT PCPN EVENT OCCURRING OVER THE GREAT LAKES/MIDWEST TOWARD THE MIDDLE OF NEXT WEEK. CURRENT MODEL RUNS SUGGEST PCPN SHOULD BE MOSTLY RAIN ACROSS THE FCST AREA FOR THE MAIN EVENT...BUT THERE IS STILL PLENTY OF UNCERTAINTY BEING SO FAR OUT IN THE FCST CYCLE AND WILL LEAVE GOING FCST AS IS WITH RAIN/SNOW. BEHIND THE SYSTEM...CONFIDENCE IS GROWING FOR THE BITTER ARCTIC AIR BUILDING IN CANADA TO SURGE INTO THE AREA FOR THE LAST HALF OF THE WEEK...SENDING TEMPS WELL BELOW NORMAL. THERE WILL NO DOUBT BE SIGNIFICANT LES AS THIS OCCURS. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ROLFSON mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CARIBOU ME 923 AM EST THU NOV 23 2006 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO MOVE TO THE EAST OF THE STATE TODAY. LOW LEVEL MOISTUIRE ALONG THE NEW BRUBSWICK BORDER WILL RESULT IN A FEW AREAS OF FREEZING FOG THIS MORNING. LOW PRESSURE OFF THE CAROLINA COAST IS EXPECTED TO MOVE TO THE EAST OF NEW ENGLAND TONIGHT. THIS LOW MAY BRING SOME RAIN TO COASTAL AND DOWNEAST AREAS LATER TODAY AND TONIGHT. && .SHORT TERM /REST OF TODAY/... HAVE DONE A QUICK UPDATE TO GRIDS AND TEXT PRODUCTS TO ADD AREAS OF FREEZING FOG FROME HOULTON TO CARIBOU TO VAN BUREN. VIS SATL SHOWS THIS AREA NICELY AND IT EXTENDS WELL EAST INTO NB. EXPECT THIS AREA TO SLOWLY ERODE MIDDAY AS LONG AS CIRRUS ALOFT STAYS THIN ENOUGH TO ALLOW SUN THROUGH. OTHER CHANGES INCLUDE REMOVING POPS FOR ZONES 15 & 16. NAM WRF WHICH IS THE MOST AGGRESIVE MODEL WITH PRECIP CONFINES QPF TO THE IMMEDIATE COAST WHILE GFS KEEP ALL QPF EAST OF THE AREA. WILL CONTINUE WITH CHANCE POPS FOR ZONES 29 & 30. WILL MAKE ONLY MINOR ADJUSTMENTS TO MARINE FORECAST TO INCORPERATE LATEST RUC WINDS. && .PREV DISCUSSION... /ISSUED 239 AM EST THU NOV 23 2006/ SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO MOVE TO THE EAST OF THE STATE TODAY. LOW PRESSURE OFF THE CAROLINA COAST IS EXPECTED TO MOVE TO THE EAST OF NEW ENGLAND TONIGHT. THIS LOW MAY BRING SOME RAIN TO COASTAL AND DOWNEAST AREAS LATER TODAY AND TONIGHT. SHORT TERM /TODAY THROUGH FRIDAY/... MAIN MAP FEATURES ARE STRONG HIGH PRESSURE OVER EASTERN NEW BRUNSWICK AND NORTHERN NOVA SCOTIA MOVING TO THE EAST AND STRONG LOW PRESSURE OFF THE CAROLINA COAST MOVING TO THE NORTHEAST. GFS SEEMS TO BE MOVING MORE IN LINE WITH NAM LAST 24 HOURS IN BRING THE LOW PRESSURE SYSTEM CLOSER TO COAST. SO WILL USE BLEND OF BOTH MODELS UNDER THE ASSUMPTION THAT BOTH WILL CONTINUE TO TREND TOWARDS A COMMON SOLUTION. HAVE CREATED THE TEMPERATURE...DEW POINT AND WIND GRIDS WITH A MAV/MET COMBINATION. FOR TEMPERATURES AND DEW POINTS OVER THE COASTAL WATERS WILL USE THE NAM12. IN THE SKY GRIDS WILL MANUALLY DRAW INITIAL GRIDS TO FIT CURRENT OBSERVATIONS THEN WILL GRADUALLY INCREASE NUMBERS FROM SOUTHEAST TO NORTHWEST ACROSS THE FORECAST AREA AS THE LOW PRESSURE SYSTEM MOVES NORTHEAST ALONG THE COAST. FOR THE POP GRIDS HAVE INITIALIZED TODAY INTO TONIGHT WITH A MAV/MET COMBINATION AND THEN FINALIZED WITH SOME SMOOTHING THEN HAVE BLENDED IN WITH PREVIOUS FORECAST POPS GOING INTO FRIDAY. QPF GRIDS HAVE BEEN INITIALIZED WITH A 50/50 NAM/GFS THEN ADJUSTED TO BETTER FIT POP GRIDS. LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... HGH PRES TO START THE LONG TERM W/ DRY CONDS AND MILD TEMPS FOR THIS TIME OF YEAR... MODEL CONSENSUS SHOWS HGH PRES RDG GRADUALLY SAGGING S AND E OF THE FA BY STA NGT W/ WEAK COLD FRONT PROGGED TO CROSS THE FA ON SUN. MADE SOME MINOR ADJUSTMENTS TO THE CURRENT GRIDS FRI NGT THRU SAT NGT W/ REMAINDER OF THE LONG TERM UNCHANGED. AVIATION... VFR CONDS ALL TAF SITES THO SOME MVFR CONDS PSBL SRN SITES LTR THIS AFTN... MARINE... THE GFS SEEMS TO BE MOVING MORE IN LINE WITH THE NAM DURING THE LAST 24 HOURS. STRATEGY WILL BE TO CREATE A BLEND OF BOTH MODEL UNDER THE ASSUMPTION THAT BOTH WILL CONTINUE TOWARD A COMMON SOLUTION...SO WILL CREATE WIND GRIDS WITH A 50/50 BLEND OF THE NAM12 AND THE GFS. FOR WAVES EXPECT FETCH ORIENTATION TONIGHT TO TREND MORE TOWARDS AN EAST/WEST AXIS TO THE EAST OF THE GULF OF MAINE. THIS IS REFLECTED IN THE SPECTRAL DATA FOR CAR01 WITH A SOUTHEAST SWELL GROUP. WHILE THIS SWELL GROUP LOOKS REASONABLE THE WIND WAVE GROUP FOR FRIDAY APPEARS A LITTLE HIGH GIVE THE FORECASTED WIND SPEEDS SO WILL ADJUST COMBINED SEA FOR FRIDAY AFTERNOON DOWN 1 FOOT. CURRENT OBSERVATIONS SHOWING SEAS 3 FT AT 44027 AND 4 FT 44034 SO WILL START SCA AT 12Z. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ050. && $$ SHORT TERM/MARINE...LULOFS me AREA FORECAST DISCUSSION...UPDATE AVIATION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 750 AM MST THU NOV 23 2006 .SYNOPSIS...A PACIFIC STORM SYSTEM WILL PUSH A COLD FRONT THROUGH NORTHERN UTAH THIS MORNING. COOL WESTERLY FLOW BEHIND THE FRONT WILL PERSIST THROUGH THE WEEKEND. A MUCH STRONGER AND COLDER SYSTEM LOOKS ON TAP FOR MONDAY. && .DISCUSSION...MEAN LONGWAVE TROUGH WHICH HAS RESIDED ACROSS THE GULF OF AK OVER THE PAST FEW DAYS CONTINUES TO SPREAD INLAND ACROSS THE PACIFIC NORTHWEST THIS MORNING. PROGRESSIVE SHORTWAVE TROUGH WITH BASE OF THE MEAN LONGWAVE CURRENTLY PROPAGATING THROUGH THE NORTHERN GREAT BASIN. IT APPEARS ASSOCIATED COLD FRONT HAS FRACTURED...WITH 700MB BAROCLINIC ZONE RACING EAST ACROSS EASTERN NV PER LATEST RUC ANALYSIS...WHILE SURFACE COLD FRONT WHICH LIKELY SLOWED AS IT CROSSED THE NORTHERN SIERRAS/CASCADES...CONTINUES TO LAG FURTHER WEST ACROSS WESTERN ID INTO NORTHWEST NV. THIS FEATURE ALSO COINCIDES WITH LEADING EDGE OF REGION OF STRONGEST MID-LEVEL ASCENT...AND IS RESULTING IN BROKEN BAND OF PRECIPITATION ACROSS NORTHERN NV AND SOUTHWEST ID. AS 700MB BAROCLINIC ZONE SPREADS EAST ACROSS WEST DESERT IT SHOULD PHASE WITH SURFACE TROUGH CURRENTLY IN PLACE...EFFECTIVELY DEVELOPING NEW SURFACE BAROCLINIC ZONE/COLD FRONT. THIS FEATURE STILL LOOKS TO CROSS WASATCH FRONT TOWARD SUNRISE...AND MAY BE ACCOMPANIED BY A WEAK BAND OF PRECIPITATION MAINLY ALONG AND NORTH OF INTERSTATE 80. REGION OF MID LEVEL ASCENT ASSOCIATED WITH PVA PROGGED TO SPREAD ACROSS FAR NORTHERN LATE THIS MORNING. EXPECT AFOREMENTIONED BAND OF PRECIPITATION ACROSS ID/NORTHERN NV ASSOCIATED WITH THIS REGION OF LIFT TO WEAKEN AS IT CONTINUES EAST...HOWEVER SHOULD HOLD TOGETHER TO BRING A PERIOD OF SNOW TO FAR NORTHERN UT. PRECIPITATION MAY INITIALLY BEGIN AS RAIN ACROSS VALLEY FLOORS OF FAR NORTHERN UT BUT SHOULD QUICKLY TRANSITION TO SNOW. MID LEVEL SUBSIDENCE PROGGED TO RAPIDLY SPREAD ACROSS NORTHERN UT BY EARLY AFTERNOON...EFFECTIVELY ENDING PRECIPITATION EXCEPT PERHAPS A FEW SHALLOW SNOW SHOWERS ACROSS THE HIGHER TERRAIN. IN THE WAKE OF THIS SHORTWAVE...FLOW BECOMES PREDOMINANTLY ZONAL THROUGH THE WEEKEND WITH A SERIES OF WEAK EMBEDDED SHORTWAVE FEATURES TRANSLATING THROUGH THE AREA BRINGING PERIODS OF MID AND HIGH LEVEL CLOUDS. LOW LEVEL MOISTURE IS EXPECTED TO REMAIN LIMITED SO NOT ANTICIPATING ANY PRECIPITATION ACROSS FORECAST AREA DURING THIS TIME. OTHERWISE WARM ADVECTION ALOFT OVERTOP OF SHALLOW COLD DOME WILL RESULT IN VALLEY INVERSIONS SETTING UP ACROSS MOST NORTHERN AND CENTRAL VALLEYS FRIDAY THROUGH SATURDAY. THESE INVERSIONS MAY BE MIXED OUT SUNDAY AS SOUTHERLY FLOW INCREASES. MOST MEDIUM RANGE MODELS ALONG WITH GFS ENSEMBLES ARE NOW DEVELOPING A VERY DEEP AND COLD LONGWAVE TROUGH OVER THE WESTERN CONUS EARLY NEXT WEEK...WITH A POTENTIALLY MAJOR WINTER STORM SETTING UP FOR THE FORECAST AREA MONDAY INTO MONDAY NIGHT. SURFACE FRONT CURRENTLY EXPECTED TO PUSH THROUGH NORTHERN UT MONDAY AFTERNOON WITH SNOW QUICKLY DEVELOPING BEHIND THIS BOUNDARY LATE MONDAY AFTERNOON THROUGH MONDAY NIGHT. VERY COLD AIRMASS PROGGED TO SETTLE INTO THE INTERMOUNTAIN WEST BEHIND THIS FRONT...WITH 700MB TEMPS PROGGED BELOW -20C BY TUESDAY NIGHT. UNCERTAINTY INCREASES SUBSTANTIALLY TOWARD MIDWEEK AS SOME MODELS ARE MORE PROGRESSIVE LIFTING TROUGH OUT OF THE REGION WHILE OTHERS /GFS/ KEEP LONGWAVE TROUGH PARKED ACROSS THE INTERMOUNTAIN REGION. FOR NOW HAVE INCREASED POPS ACROSS REGION MONDAY THROUGH MONDAY NIGHT...AND RETAINED CHANCE POPS THROUGH TUESDAY FOR HIGHER TERRAIN AS WELL AS THE WASATCH FRONT. && .AVIATION...COLD FRONT MOVED THROUGH WENDOVER JUST BEFORE 14Z THEREFORE HAVE DELAYED ARRIVAL TIME OF COLD FRONT AT SLC TO 1730Z BASED ON THE TYPICAL 4 HR TRAVEL TIME FROM WENDOVER. PRECIP IS LAGGING ABOUT 2 HOURS BEHIND THE COLD FRONT AND IS ONLY A NARROW BAND WHICH WILL LAST LESS THAN TWO HOURS. THERE IS A 30 PERCENT CHANCE OF MVFR CONDITIONS DUE TO CEILINGS. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && $$ SEAMAN/STRUTHWOLF FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE) ut AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1103 AM EST THU NOV 23 2006 .SHORT TERM /REST OF TODAY/... ONLY MINOR UPDATE TO THIS MORNING/S FCST TO REFLECT LATEST SAT/RADAR TRENDS...AND TO TWEAK MAX TEMPS SLIGHTLY. SFC LOW EAST OF THE VA CAPES CONTINUES TO LIFT SLOWLY NE TOWARDS THE OUTER 40/-70 BENCHMARK THIS MORNING BASED ON LATEST 3 HRLY PRESSURE FALLS. ASSOC PCPN SHIELD CONTINUES TO ATTEMPT TO ADVANCE NORTH/NORTHWESTWARD...THOUGH IS DISSIPATING AS IT RUNS INTO MUCH DRIER AIR AND STRONG SUBSIDENCE ASSOC W/SEMI-STATIONARY SFC TO MID LVL RIDGE AXIS ORIENTED ACROSS THE SLV. THUS HAVE EASED POPS BACK SLIGHTLY ACROSS SRN TWO COUNTIES TODAY AND THIS EVENING...AND OFFERED DRY CONDS FURTHER NORTH. LATEST LAPS/ACARS/RUC SOUNDING PROFILES CONTINUE TO SHOW STRONG SYNOPTIC INVERSION ACROSS AREA THIS MORNING...WITH FAIRLY LOW AFTERNOON PBL MIXING HEIGHTS. THIS SHOULD TRANSLATE INTO VERY UNIFORM TEMP RANGE IN THE LOW TO MID 40S ACROSS THE CENTRAL/NORTH TODAY UNDER FULL TO PARTIAL SUN...WITH EVEN HIGHER SUMMIT LOCALES REACHING SIMILAR VALUES. OTW INHERITED FCST IN EXCELLENT SHAPE AND NO OTHER CHGS NEEDED. ENJOY THE DAY. && .PREV DISCUSSION... /ISSUED 510 AM EST THU NOV 23 2006/ SHORT TERM /TODAY THROUGH SATURDAY/... THE WOBBLES AND HICCUPS (TRACK AND TIMING) EXPERIENCED BY THE MDLS SOME 24-48 HRS AGO HAVE GONE AWAY AS MDLS HV BCM MORE CONSISTENT DRG THE PAST 24 HRS WITH A CONSENSUS TRACK OF ATLANTIC COASTAL SMLR TO THAT OF 2-4 DAYS AGO...ARD 40N/70W BENCHMARK AND THE TIMING HAS OBVIOUSLY BEEN SPED UP FM FRI-FRI NGT TO TDY. CRNTLY...SFC LOW OFFSHORE OF NC AND SLOWLY MVG NNE WITH RAINBANDS ALRDY ACRS SNE SHORELINE AND LIKE THE NAM SOLN/PARAMETERS BRINGING PCPN TO VT/MA BDR ARD 12Z AND PERHAPS REACHING SRN RUTLAND/WINDSOR BTWN 12-18Z BFR EXITING E. THIS SOLN IS VRY SMLR TO YDY THINKING AND THUS NO REAL CHGS TO FCST. BASICALLY...FOR US NOT ANY MJR PRBLMS AND MAY TOTALLY ESCAPE ANY PCPN BUT POINTS S WL BE WET AND PSBLY INITIALLY SOME FZRA AS WELL. WE/VE HIGHLIGHTED THESE CHANGES AND PSBLTYS WITH A SPSBTV ON MIDSHFT AND DAYSHFT YDY FOR TRAVELERS INTO SRN VT AND POINTS S AND FEEL WE/RE AHD OF THE GAME. THEREAFTER...SW-NE ELONGATED RDG FM THE GULF COAST BUILDS INTO ERN GRT LAKES AND NE FRI/SAT WITH SFC HIGH ACRS FA AS WELL. ULVL RDG AXIS AND SFC HIGH SHIFT SLIGHTLY SE ACRS MID-ATLANTIC STATES LATE SAT. MDL T FCSTS HAVE HAD HUGE RANGES (BTWN MDLS UP TO 15F) AT SOME MTN VLY LOCALES FOR MINS AND MAXES FOR SVRL DAYS AND HAVE DONE WELL SO FAR STAYING AWAY FM EXTREME LOWS. TDY...MAX T AT KBTV ON ETA MOS IS 56F VS. 42F ON GFS MOS. YES...SOME CLD DFRNCS BUT 925MB TMPS ARE SMLR ABT 1-2C MILDER THAN WED AND WL BASE TDYS MAX ON THAT AS WELL AS CLDS/PCPN. ON FRI...DECENT N FLOW AND CAA WITH DEPARTING COASTAL WITH COLDER TMPS LKLY IN NRN CHMPL VLY AND NE VT WITH MILDER IN DOWNSLOPE REGIONS. MDLS CONSISTENT WITH A NICE LATE AUTUMN DAY ON SAT WITH TMPS ARD 50F. LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ULVL RDG AND SFC HIGH ELONGATED SW-NE FM GULF TO MID-ATLANTIC WITH WEAK IMPULSES RIDING ALG NRN PERIPERHY WITH A WEAK BNDRY ACRS GRT LAKES. THE MDLS DIFFERENT SLGTLY ON WHETHER ANY S/W IN RELATIVELY FLAT-ZONAL NRN STREAM HELPS DROP BNDRY INTO FA. ATTM...IT LOOKS LIKE NRN FA IS THREATENED BY A FEW MORE CLDS AWAITING TWO DISTURBANCES. THE FIRST BEING A NRN STREAM S/W THAT STAYS WELL N OF FA WITH THE ABV MNTD BNDRY WASHING OUT. THE SECOND IS THE OUTCOME OF STG...COLD CLOSED LOW IN PAC NW THAT WL BRG FIRST ARCTIC SURGE ACRS PAC NW/NRN ROCKIES THEN ROTATE ENE ACRS CANADA WITH AN ASSOCIATED/TRAILING CD FNT MVG TOWARD FA FOR MID-WK. IN ADDITION...S/W ENERGY DROPPING ACRS ROCKIES CUD DVLP LEE-SIDE LOW THAT WUD TRAVEL ALG THIS BNDRY TOWARD GRT LAKES FOR MID WK. ATTM...CRNT FCST HAS MNTN OF PCPN FOR TUES NGT/WED SO NO UPDATES IN LONGER TERM NEEDED. AVIATION... VFR COND EXPECTED AT ALL SITES WITH MAINLY A SCT-BKN MID DECK AROUND 120-150. SOME LOW CLD AFT 15Z-16Z FOR KBTV/KMPV DUE TO VICINITY OF LOW MVG UP COAST W/ KMPV GOING BKN035 FOR A FEW HRS...BUT NO PRECIP. AREAS WILL REMAIN VFR AFT 00Z W/ P6SM SKC...KMPV WILL SEE SKC CLOSER TO 02Z-03Z. WINDS N/NE LESS THAN 10 KTS...W/ LGT/VAR AT TIMES BFR 12Z AND AFT 00Z FRI. HIR TRRN WILL BE OBSCD CLOSER TO KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SHORT TERM...JMG vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1045 AM CST THU NOV 23 2006 .DISCUSSION... LIKE YESTERDAY...FORECAST LOOKS ON TRACK FOR TODAY AND ONLY MINOR UPDATE TO THE GRIDS. IDEAL WEATHER CONDITIONS PREVAIL AGAIN ON THIS THANKSGIVING DAY FOR TRAVELERS. SUNNY SKIES WITH JUST A FEW THIN CIRRUS CLOUDS PASSING BY WITH HIGHS IN THE UPPER 50S AND LOWER 60S WITH SOUTH WINDS 5 TO 15 MPH. 16Z/10 AM SURFACE MAP SHOWS 1034 MB HIGH PRESSURE OVER NEW BRUNSWICK CANADA AND RIDGING SW ACROSS THE LOWER OHIO AND MS VALLEYS...ABOUT THE SAME POSITION AS IT WAS 24 HOURS AGO. ALOFT A 587 DM 500 MB HIGH WAS OVER THE WESTERN GULF OF MEXICO AND RIDGING NORTH INTO IL. SURFACE AND UPPER LEVEL RIDGE NEAR IL CONTINUING SUNNY SKIES ACROSS IL THIS MORNING. TEMPS WERE IN THE UPPER 40S AND LOWER 50S WITH MILDER READINGS FROM LINCOLN SW. DRY DEWPOINTS IN THE LOWER 30S WITH SSE WINDS 3 TO 10 MPH. RUC AND NAM/WRF SHOWS SURFACE AND UPPER LEVEL RIDGE SLOWLY SLIDING TOWARD THE EASTERN STATES FRI AND WILL CONTINUE TO CONTROL ILLINOIS WEATHER WITH AMPLE SUNSHINE WITH JUST SOME THIN CIRRUS CLOUDS MOVING IN THIS AFTERNOON AND MILDER TEMPS. MIXING UP TO 950 MB GIVES HIGHS IN THE UPPER 50S EAST AND LOWER 60S WEST TODAY WITH ILX AT 60F. NORMAL HIGHS ARE 45 TO 50F. && .PREV DISCUSSION... A RATHER WARM TURKEY DAY ON TAP ACROSS THE REGION. THIS WARM TREND SHOULD CONTINUE THROUGH THE WEEKEND... EVEN AS A WEAK COLD FRONT APPROACHES FRIDAY AND STALLS OUT OVER NORTHWESTERN ILLINOIS. THIS FRONT WILL PLAY A MAJOR ROLE IN THE WEATHER THROUGH EARLY NEXT WEEK AS A PATTERN SHIFT GETS UNDERWAY... CULMINATING WITH A RATHER STRONG STORM SYSTEM BY MIDWEEK WHICH SHOULD USHER IN A SHOT OF COLDER AIR. SHORT TERM...TODAY THROUGH SUNDAY... HAPPY THANKSGIVING. IT WILL BE ANOTHER UNSEASONABLY MILD DAY ACROSS THE CWA TODAY. STILL DEALING WITH A STRONG INVERSION ALOFT WHICH WILL LIMIT MIXING POTENTIAL AS WELL AS SOME SCATTERED CIRRUS... BUT EVEN SO WE SHOULD GAIN ANOTHER 2-3 DEGREES ON YESTERDAYS HIGHS. EXPECT WE WILL CRACK THE 60 DEGREE MARK SOMEWHERE SOUTHWEST OF A HAVANA-LINCOLN-DECATUR LINE. CUTOFF LOW OFF THE OUTER BANKS WILL MAKE SLOW PROGRESS FOR CAPE COD AND EVENTUALLY OPEN UP AS IT HEADS INTO THE MARITIMES. BEHIND IT... STRONG RIDGING OVER THE GULF OF MEXICO WILL BUILD NORTHEAST ALONG THE EASTERN SEABOARD... WHILE BROAD TROUGHING SETS UP ACROSS THE NORTHWESTERN QUARTER OF THE COUNTRY. A WEAK COLD FRONT WILL APPROACH THE AREA AND STALL OUT JUST TO OUR NORTHWEST FRIDAY AFTERNOON... STILL NO PRECIP EXPECTED WITH DRY CONDITIONS PREVAILING. WITH SOUTHWEST FLOW ALOFT... WE WILL REMAIN ABOVE NORMAL WITH TEMPS THROUGH THE WEEKEND. HOWEVER... A NUMBER OF DISTURBANCES LOOK TO PASS THROUGH THE AREA BEGINNING SATURDAY. MEANWHILE... RETURN FLOW FROM AN OPEN GULF WILL BRING BACK THE MOISTURE. GFS HAS BEEN CONSISTENTLY ADVERTISING SCATTERED QPF ALONG THE STALLED OUT FRONT SATURDAY... BUT STILL THINK THE ATMOSPHERE WILL BE TOO DRY AT THAT POINT. SHOULD SEE INCREASING CLOUDS ACROSS THE NORTHWEST SATURDAY AFTERNOON NEAR THE FRONT AS MOISTURE SLOWLY ARRIVES. BETTER CHANCES FOR RAIN WILL ARRIVE BY SUNDAY NIGHT... AIDED BOTH BY RICHER MOISTURE AND THE LEADING EDGE OF A RATHER STRONG SUBTROPICAL BRANCH OF THE JET STREAM. PRECIP SHOULD REMAIN NEAR THE FRONT NORTH AND WEST OF THE ILLINOIS RIVER. LONG TERM...MONDAY THROUGH WEDNESDAY... BIGGEST CHALLENGE WILL BE WHERE THE FRONTAL BOUNDARY IS SET UP BY EARLY NEXT WEEK. AS WEST COAST TROUGH SHIFTS EAST... STRONG LEE CYCLOGENESIS WILL TAKE PLACE OVER THE PLAINS... AND INCREASING LOW LEVEL SOUTHERLY FLOW OUT AHEAD OF THIS SYSTEM SHOULD SLOWLY LIFT THE BOUNDARY TO THE NORTH... BUT AT THE SAME TIME RESULT IN INCREASING ISENTROPIC LIFT. WILL LEAVE CHANCE POPS IN MONDAY AND TUESDAY. AS THE TROUGH EJECTS OUT... A RATHER STRONG STORM SYSTEM IS EXPECTED TO MOVE ACROSS THE PLAINS AND TO OUR NORTH... BRINGING PLENTY OF COLD AIR BEHIND IT. MODELS ARE IN DECENT AGREEMENT... AND STILL PREFER THE WEDNESDAY FROPA SOLUTION... DESPITE THE 00Z ECMWF SPEEDING UP A LITTLE BIT. HIGHLY AMPLIFIED PATTERN WITH STRONG RIDGING ACROSS THE EAST COAST PROMOTES SLOWER MOVEMENT OF THE OVERALL PATTERN. MAIN QUESTION WILL BE HOW FAR NORTH AND WEST OF US WILL THE BULK OF THE ENERGY WITH THE TROUGH AND THE ATTENDANT SFC LOW GO. A FARTHER SOUTH TRACK SUGGESTS GREATER QPF AMOUNTS... BETTER CONVECTIVE AND POSS SVR POTENTIAL. A FARTHER NORTH TRACK WOULD DECREASE OVERALL SHEAR. WITH SUCH A STRONG FRONT... PRECIP LOOKS LIKE A DECENT BET... SO INCREASED POPS ON DAY 7 PERHAPS A LITTLE HIGHER THAN USUAL CONSIDERING THE HIGHER THAN NORMAL CONFIDENCE. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ HUETTL/HARDIMAN il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 235 PM CST THU NOV 23 2006 .SHORT TERM...TONIGHT THROUGH 00Z SUNDAY. MAIN FORECAST PROBLEM FOR THIS PERIOD WILL BE TEMPERATURES INITIALLY...THEN CHANCE FOR SHOWERS OR DRIZZLE SATURDAY AND SUNDAY. LATEST WATER VAPOR IMAGERY REVEALED A DECENT SHORT WAVE MOVING THROUGH THE PACIFIC NORTHWEST. 12Z UPPER AIR ANALYSIS INDICATED ABOUT 90 METER HEIGHT FALLS. BEST DYNAMICS AND MOISTURE WILL WILL THROUGH THE NORTHERN PLAINS OVERNIGHT. FOR US...THE WAVE WILL PICK UP A LEE TROUGH AND DRIVE THAT SOUTH AS A COLD FRONT OVERNIGHT. THUS...TODAY SHOULD BE THE LAST REALLY WARM DAY...BUT STILL SEVERAL DAYS OF ABOVE NORMAL TEMPERATURES EXPECTED THROUGH THE WEEKEND WITH HIGHS STILL IN THE 50S. AHEAD OF THE FRONT TONIGHT...WE WILL STILL SEE PARTLY CLOUDY SKIES AS PACIFIC MOISTURE CONTINUES TO STREAM OVERHEAD. FEEL THAT SOME PATCHY FOG WILL ALSO DEVELOP AHEAD OF THE COLD FRONT GIVEN THAT SURFACE DEWPOINTS ARE CURRENTLY IN THE LOWER 40S ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. ONCE THE FRONT ARRIVES THOUGH...THE FOG SHOULD CLEAR OUT QUICKLY...THUS TRIED TO TIME THE FOG IN THE GRIDS BASED ON FROPA. WOULD NOT BE SURPRISED TO SEE A NARROW BAND OF STRATUS DEVELOP RIGHT AHEAD OF THE FRONT IN TANDEM WITH THE FOG...AND WOULD ALSO NOT BE SURPRISED TO SEE SOME LOCALLY DENSE FOG ACROSS SOUTHWEST IOWA OR EXTREME SOUTHWEST NEBRASKA BASED ON BUFKIT SOUNDINGS AND NAM/RUC VISIBILITY FORECASTS. CLEAR SKIES AND LIGHT WINDS SHOULD PRECLUDE WIDESPREAD DENSE FOG THOUGH. THE AFOREMENTIONED FRONT SETS UP ACROSS KANSAS AND MISSOURI ON FRIDAY. WE SHOULD REMAIN DRY BUT COOLER...AGAIN WITH A VEIL OF CIRRUS CLOUDS OVERHEAD. THE FRONT WILL BECOME THE FOCUS FOR PRECIPITATION THROUGH EARLY NEXT WEEK. MOISTURE SHOULD POOL ALONG THE FRONT FRIDAY NIGHT AS IT BEGINS TO LIFT BACK NORTH AS A WARM FRONT. COULD SEE SOME SPRINKLES OR DRIZZLE DEVELOP NEAR THE FRONT BY EARLY SATURDAY ACROSS EXTREME SOUTHEAST NEBRASKA/SOUTHWEST IOWA... THEN A SLIGHT CHANCE OF MEASURABLE RAIN ALONG THE FRONT THROUGH THE DAY SATURDAY AS A WEAK IMPULSE MOVES OUT OF THE FOUR CORNERS REGION...SHIFTING EASTWARD INTO IOWA BY SATURDAY EVENING. THE FRONT APPEARS TO LIFT TOWARD THE SOUTH DAKOTA BORDER SATURDAY NIGHT WHILE LOW LEVEL MOISTURE STREAMS NORTHWARD INTO THE REGION. FEEL THAT LOW CLOUDS AND FOG WILL DEVELOP WITH IFR CONDITIONS... ALTHOUGH THE MID LEVELS REMAIN DRY. THUS...AM EXPECTING SOME PATCHY DRIZZLE AS ISENTROPIC LIFT DEVELOPS OVERNIGHT BUT CHANCE FOR MEASURABLE RAINFALL DURING THIS TIME LOOKS PRETTY SLIM. FEEL THE NAM IS WAY OVERDONE ON ITS PRECIP AT THIS TIME GIVEN THAT I BELIEVE IT'S LIFTING THE VORT MAX OUT TOO FAST IN THE MEAN SOUTHWEST FLOW ALOFT. THIS WAVE SHOULD MOVE ONTO THE PLAINS SUNDAY...WHICH SHOULD BRING BACK A CHANCE OF MORE MEASURABLE RAIN AS THE FRONT THEN GETS PUSHED BACK SOUTH TOWARD KANSAS AND MISSOURI SUNDAY EVENING. DEWALD .LONG TERM...00Z SUNDAY THROUGH THURSDAY. MAIN QUESTIONS REMAIN ARCTIC FRONTAL TIMING AND PCPN CHCS...GENERALLY AHEAD OF IT. CONTINUED SMALL POPS IN SUN NGT/MONDAY PERIOD AS GFS AND 00Z ECMWF BROUGHT A WEAK SFC FRONT THROUGH FCST AREA LATE SUNDAY AND THEN SET UP POTENTIAL FOR ISENTROPIC LIFT N OF IT AS FRONT STALLS OUT AND ATTEMPTS TO LIFT BACK N. POPS COULD EVEN INCREASE A BIT LATE MON/MON NGT AS SOME ELEVATED INSTABILITY WAS OBSERVED BY GFS TO CREEP INTO ERN ZONES AS LEFT FRONT EXIT REGION OF THE UPPER JET NOSES TOWARD NERN NEBRASKA LATE MONDAY NIGHT. WILL GENERALLY KEEP MAX TEMPS MONDAY BELOW MEX GUIDANCE BECAUSE OF CLOUD POTENTIAL...AND IT WAS NOTED THAT 12Z MEX NUMBERS WERE A CATEGORY OR SO COLDER THAN 00Z. ALSO WITH LOW LVL MOISTURE RETURNING A BIT MONDAY NIGHT ...RAISED LOWS AHEAD OF ARCTIC FRONT. FRONTAL TIMING TUESDAY WILL PLAY AN OBVIOUS ROLE IN MAX TEMPS...BUT BECAUSE OF A DECENT CHC THAT LOWS COULD TURN OUT EVEN WARMER THAN THOSE THAT WILL BE FORECAST IN THIS SET...DECIDED TO RAISE HIGHS A BIT...ESPECIALLY SINCE 12Z GFS WAS EVEN A BIT SLOWER WITH FROPA THAN 06Z RUN WAS. ALTHOUGH AM SOMEWHAT LEARY OF A SLOWER PASSAGE SINCE ONCE ARCTIC FRONTS START MOVING SEWD THEY SEEM TO MOVE A BIT FASTER THAN MODELS GIVE THEM CREDIT. KEPT IN SMALL PCPN CHCS POST FRONTAL AS A BIT OF 500-300 QG FORCING WAS FCST BY GFS...SPED UP CHANGE TO SNOW HOWEVER. BEYOND TUESDAY LOWERED TEMPS TUE NGT THROUGH WED NGT AS AIRMASS IN WRN CANADA IS QUITE COLD AND TRENDS OF GFS MOS GUIDANCE HAS BEEN COLDER WITH EACH SUCCESSIVE RUN. RIGHT REAR ENTRANCE REGION SHIFTS ACROSS FCST AREA WED AS TROUGH SWINGS EWD ACROSS ARCTIC AIRMASS WHICH SHOULD BE IN PLACE BY THEN...THUS ADDED FLURRIES TO FORECAST WED. COLD AND DRY CONDITIONS SHOULD PREVAIL NEXT THURSDAY. CHERMOK && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ ne