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000 FXUS62 KTAE 030759 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 230 AM EST MON NOV 3 2008 .SYNOPSIS... AT 2 AM EDT...SKIES RANGED FROM MOSTLY CLOUDY ACROSS S/CNTRL GA TO MOSTLY CLEAR ELSEWHERE. TEMPERATURES RANGED FROM LOW 50S SE ALA/SW GA TO NEAR 60 PANHANDLE COAST. 24 TEMP/DEW POINT COMPARISON INDICATES THAT LOCAL AIRMASS MODESTLY MILDER AND MOISTER THAN SAME TIME YESTERDAY. WINDS WERE GENERALLY NE 5-7 MPH. AT UPPER LEVELS... CONUS PICTURE OVERNIGHT HIGHLIGHTED BY TROUGH JUST OFF PAC NW...ANOTHER OVER INTERMOUNTAIN/ROCKIES REGION...A RIDGE OVER PLAINS AND ANOTHER TROUGH OVER ERN CONUS. AS ERN PAC SYSTEM MOVES ONSHORE LATER TODAY...DOWNSTREAM TROUGH MOVES INTO HIGH PLAINS SHUNTING RIDGE AND ERN TROUGH EWD WITH TROUGH AND ASSOCIATED LOW INTO WRN ATLC. CLOSER TO HOME...UPPER AIR DATA AND VAPOR IMAGERY CONTINUES TO SHOW WEAK MID/UPPER LOW DRIFTING ENE ACROSS OUR REGION. AT 06 UTC THE 500 MB CENTER WAS LOCATED JUST EAST OF TALLAHASSEE. A SPOKE OF ENERGY EAST OF THE LOW PRODUCED SCATTERED SHOWERS AND ISOLD TSTMS OVER THE COASTAL WATERS ON SUNDAY. OVERNIGHT...SPOKE/ASSOCD PRECIP MOVED EAST OF CWA. THE PROFILE ALOFT HAS COOLED...AS YOU WOULD EXPECT WITH THE UPPER LOW NEARBY...WITH SOME WEAK ELEVATED INSTABILITY PRESENT. THE AIRMASS HAS MOISTENED WITH 00Z RAOB SHOWING THAT THE PRECIPITABLE WATER NOW UP TO 1.11 INCHES. UPPER LOW FORECAST TO MOVE FROM NE FL/SE GA TO THE COAST AND MEANDER DURING MORNING BEFORE MOVING NEWD TO THE COASTAL CAROLINAS TONIGHT..LEAVING DRY AIR IN ITS WAKE ACROSS LOCAL REGION. RIDGING MOVES ACROSS THE REGION THROUGH WEDNESDAY WHILE A STRONG SYSTEM ADVANCES ACROSS THE PLAINS(SEE EXTENDED DISCUSSION). AT LOWER LEVELS... SURFACE ANALYSIS SHOWS AN INVERTED TROF JUST OFF THE FLORIDA EAST COAST AND OVER THE BAHAMAS. THE NE MOVING UPPER LOW ALREADY INTERFACING WITH THIS TROUGH TO GENERATE THE BEGINNING OF A SURFACE LOW AS INDICATED BY VARIED WIND DIRECTIONS (I.E. N FLOW WEST OF TROUGH AND E FLOW EAST OF TROUGH). THIS LOW WILL TRACK TO NC COAST THRU TUE WITH HIGH PRES BUILDING IN ITS WAKE. SPECIFICALLY...A 1037 MB HIGH IS LOCATED OVER SOUTHERN NEW ENGLAND THIS MORNING. UNDER INFLUENCE OF POLAR JET...HIGH WILL DROP TO THE MID-ATLC COAST LATER TODAY WITH ASSOCIATED RIDGING EXTENDING DOWN THE LEE SIDE OF THE APPALACHIANS AND INTO WESTERN GEORGIA. THIS COMBINATION OF HIGH DROPPING SOUTH WITH WEAK WEDGE DEVELOPMENT PLUS AND INCREASINGLY VERTICALLY STACKED LOW WILL GENERATE INCREASING NORTHEAST FLOW ACROSS OUR REGION TODAY. ITS WILL ALSO DRY OUT LOCAL AIRMASS BUT ...UNDER LOW LEVEL NE FLOW...MUCH MORE SLOWLY AT LOWER LEVELS. THIS REFLECTED IN MODEL SOUNDINGS. I.E. GFS TAE WITH 1.05 IN PWAT AT 12Z MON DROPPING TO 0.61 INCH PWAT AT 18Z. .SHORT TERM (TODAY THROUGH WEDNESDAY).. WITH DEEP LAYER LOW PROGGED TO MOVE NORTHEAST AND AWAY FROM OUR REGION THRU TOMORROW. UPPER LOW OPENS INTO A TROUGH AS IT CONTINUES ALONG THE EAST COAST WITH THE INVERTED TROUGH MOVING ALONG IN IT`S WAKE. THEN...AN UPPER RIDGE BUILDS NORTH ACROSS THE GULF AS THE SURFACE RIDGE FROM THE ALONG ERN SEABOARD STARTS TO SLIDES EAST. THUS GRADUALLY DECREASING CLOUDS AND NO POPS THRU WED. WRAP AROUND MOISTURE THROUGH THIS AFTERNOON AND CLOUDS MOVING SW UNDER ABOVE NORMAL NE FLOW THRU TUES MORNING WILL YIELD MOSTLY CLOUDY ERN ZONES. TEMPERATURES WILL REMAIN MOSTLY STATUS QUO THE NEXT FEW DAYS WITH LIGHT NORTHERLY FLOW IN PLACE IN THE WAKE OF THE DEVELOPING EAST COAST SYSTEM. HOWEVER COMPARED WITH RECENT DAYS...HIGHER SFC DEWPOINTS...INCREASING EASTERLY FLOW AND RESULTANT CLOUD COVER FROM E-W WILL RESULT IN MILDER NIGHTS AND JUST SLIGHTLY COOLER DAYS ESPECIALLY EAST OF APALACHICOLA RIVER. TODAY...INLAND HIGHS FROM LOW 70S UNDER CLOUDY EAST TO MID 70S UNDER MOSTLY SUNNY WEST. WITH CLOUDS SPREADING SW...PATCHY FOG AND STRATUS GOOD BET TONIGHT MAINLY ERN ZONES. TUESDAY...WITH CLOUDS DECREASING...INLAND HIGHS IN MID 70S. WEDNESDAY...WITH MOSTLY SUNNY SKIES...INLAND HIGHS MID-UPPER 70S. .LONG TERM...THURSDAY THROUGH MONDAY...THE WEAK UPPER RIDGE WILL BE REPLACED BY A DEEPENING TROUGH WITH AXIS TRANSLATING FROM THE PLAINS ON THURSDAY TO THE EAST COAST BY LATE SATURDAY. THE TROUGH THEN MOVES OFF THE EASTERN SEABOARD SUNDAY WITH THE UPPER FLOW BECOMING ZONAL OVER THE LOCAL REGION SUNDAY INTO EARLY NEXT WEEK. AT THE SURFACE...HIGH PRESSURE OVER THE SOUTHEAST CORNER OF THE U.S. WILL WEAKEN AND MOVE EAST THURSDAY AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT IS FORECAST TO PUSH THROUGH FRIDAY INTO SATURDAY MORNING BRINGING A CHANCE OF SHOWERS AND POSSIBLY AS FEW THUNDERSTORMS TO THE REGION. ALTHOUGH FORECAST QPF AMOUNTS DON`T LOOK IMPRESSIVE...ITS LOOKING LIKE MOST AREAS SHOULD RECEIVE SOME RAIN WITH THIS FRONT. WILL BUMP POPS UP AT LEAST INTO THE MID RANGE CHANCE CATEGORY. OUR BRIEF WARM SPELL WILL COME TO AN END WITH PASSAGE OF THE FRONT. TEMPS WILL DROP BELOW CLIMO OVER THE WEEKEND INTO MONDAY BUT NO FREEZING TEMPS ARE EXPECTED. && .AVIATION...EXPECT MID AND HIGH LEVEL CLOUDS THROUGH DAYBREAK FOR MOST TAF SITES. THERE WILL BE OCCASIONAL MVFR/IFR CIGS AT VLD AND ABY AND POSSIBLY TLH. CIGS/VSBYS IMPROVE TO VFR ALL AREAS BY LATE MORNING AS AN UPPER LEVEL SYSTEM LIFTS NORTHEASTWARD TOWARDS THE CAROLINAS. && .MARINE...WITH THE SURFACE LOW SPINNING UP OFF THE FLORIDA EAST COAST...AND NEW ENGLAND HIGH BEGINNING TO WEDGE DOWN EAST COAST...LOCAL NE GRADIENTS HAVE TIGHTENED. HOWEVER OFFSHORE WINDS THAT WERE AROUND 20 KNOTS UNTIL AROUND MIDNIGHT HAVE INCHED DOWN LAST 3-4 HRS TO BELOW ADVISORY LEVELS. THEREFORE WILL DOWNGRADE OFFSHORE SCA TO EXERCISE CAUTION LEVELS WITH NO HEADLINES NEARSHORE. AS LOW MOVES NNE THRU TUESDAY...GRADIENT SHOULD RELAX WITH LIGHTER WINDS PREVAILING BY WEDNESDAY. WINDS MAY BEGIN TO INCREASE AGAIN ON FRIDAY AHEAD OF NEXT COLD FRONT. && .FIRE WEATHER...WHILE DRIER AIR WILL FILTER INTO THE REGION THE NEXT FEW DAYS, MINIMUM RH VALUES EACH AFTERNOON WILL REMAIN ABOVE CRITICAL THRESHOLDS. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 76 54 76 50 / 0 0 0 0 PANAMA CITY 76 58 76 58 / 0 0 0 0 DOTHAN 74 52 76 51 / 0 0 0 0 ALBANY 74 53 75 51 / 0 0 0 0 VALDOSTA 73 55 73 51 / 10 0 0 0 CROSS CITY 76 54 75 51 / 10 0 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...NONE. && $$ BLOCK/BARRY