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000 FXUS62 KTAE 121835 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 235 PM EDT SUN OCT 12 2008 .SYNOPSIS...ELY FLOW IN LOW/MID LEVELS CONTINUES TO ADVECT ATLANTIC MOISTURE INTO THE TRI-STATE REGION. A COASTAL TROUGH REMAINS PARKED OFF THE GA/FL COAST, WITH A MID-LEVEL LOW CENTERED ALONG THE ERN FL PANHANDLE COAST. PERSISTENT OVERCAST IS BEGINNING TO BREAK OVER SE GA AND NRN FL. THESE BREAKS ARE ALLOWING SOME INSOLATION TO DESTABILIZE THE ATMOSPHERE. SHOWERS AND EVEN A FEW TSTMS ARE MOVING WWD INTO THESE AREAS, AND WILL EVENTUALLY AFFECT OUR GA AND ERN BIG BEND ZONES THIS AFTERNOON. TEMPS RANGE FROM A PLEASANT 70 AT DHN TO 85 AT CTY. OVER THE MARINE AREA, SUSTAINED E-NE WINDS 15-20 KTS AND GUSTY CONTINUE DUE TO THE SURFACE PRESSURE GRADIENT BETWEEN THE TROUGH TO THE EAST AND A BUILDING RIDGE TO THE NORTH. && .SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...MID LEVEL LOW AND ASSOCIATED VORT LOBES WILL CONTINUE TO PROGRESS SLOWLY WWD ACROSS THE GULF COAST THROUGH MONDAY. THE COASTAL TROUGH WILL WEAKEN AS IT ALSO TRANSLATES WWD DURING THE NEXT 12 TO 24 HOURS. MOIST CONVERGENT FLOW AHEAD OF THE TROUGH WILL KEEP SLIGHT TO LOW CHANCE POPS IN THE FCST TONIGHT AND MONDAY. STRONG HIGH PRESSURE AT THE SURFACE AND ALOFT WILL THEN BUILD OVER THE ERN STATES BY TUESDAY, WITH A RETURN TO WARMER AND DRIER CONDITIONS. THE TIGHTER SURFACE PRESSURE GRADIENT WILL GENERATE OCCASIONALLY BREEZY E-NE WINDS ON MONDAY AND LIGHTER WINDS FOR TUESDAY AS THE RIDGE WEAKENS AND ITS CENTER SETTLES OVER THE SE. SPLIT THE POP DIFFERENCE BETWEEN THE NAM AND GFS MOS, AND APPLIED AN AVERAGE OF THE MOS TEMP GUIDANCE. && .LONG TERM (WEDNESDAY THROUGH SUNDAY)...BETTER AGREEMENT THIS MODEL CYCLE BETWEEN THE GFS AND 12Z ECMWF. BOTH MODELS SHOW DEEP LAYER RIDGING AND A VERY DRY AIR MASS IN PLACE ON WEDNESDAY. THE FLOW BECOMES ZONAL THURSDAY AS A TROUGH DEVELOPS AND DEEPENS OVER THE CENTRAL CONUS. THE TROUGH CONTINUES TO AMPLIFY AS IT MAKES ITS WAY TOWARD THE EASTERN CONUS. THE ECMWF SOLUTION SHOWS A SLOWER AND DEEPER TROUGH PUSHING INTO THE SOUTHEAST SATURDAY WITH A MORE POTENT COLD FRONT CROSSING OUR CWA DURING THE DAY. THE GFS SOLUTION IS ABOUT 12 TO 18 HOURS FASTER DEPICTING A MOISTURE STARVED FRONTAL PASSAGE FRIDAY NIGHT AND EARLY SATURDAY. BOTH MODELS THEN SHOW HIGH PRESSURE AND A COOLER DRIER AIR MASS FILTERING IN ON SUNDAY. WILL LEAN TOWARD THE DRIER GFS SOLUTION. THUS, NO POPS FOR THE EXTENDED PERIOD. TEMPS WILL BE ABOVE CLIMO THROUGH FRIDAY, FOLLOWED BY MORE SEASONAL TEMPS NEXT WEEKEND. && .AVIATION...LOW CLOUD DECK CONTINUES TO GENERATE MVFR CONDITIONS AT MOST TERMINALS WITH IFR CONDITIONS AT KDHN. SOME BREAKS ARE EVIDENT OVER NORTHEAST FLORIDA/SOUTHEAST GEORGIA AND THIS SLIGHT DRYING WILL MOVE INTO KVLD AND KABY THIS AFTERNOON. THESE SITES MAY SEE SOME BRIEF BREAKS IN THE OVERCAST THIS AFTERNOON BEFORE THE CLOUDS REDEVELOP TONIGHT. MVFR/IFR CONDITIONS EXPECTED ONCE AGAIN TONIGHT WITH MOIST EASTERLY FLOW CONTINUING. && .MARINE...A COASTAL TROUGH OFFSHORE OF THE FLORIDA EAST COAST WILL ADVANCE INLAND AND WEAKEN THROUGH TONIGHT. STRONG HIGH PRESSURE WILL THEN BUILD OVER THE MID-ATLANTIC AND SOUTHEASTERN STATES THROUGH TUESDAY WHICH WILL PRODUCE A STRONG EASTERLY FLOW AND BUILDING SEAS. EXPECT CAUTIONARY TO ADVISORY CONDITIONS OVER THE COASTAL WATERS DURING THIS TIME PERIOD. THE WINDS AND SEAS WILL DIMINISH BY WEDNESDAY AS HIGH PRESSURE WEAKENS AND SINKS SOUTH OVER THE AREA. && .FIRE WEATHER...THE LOW LEVEL AIR MASS WILL GRADUALLY DRY OUT BY THE MIDDLE OF THE WEEK AS HIGH PRESSURE BUILDS OVERHEAD. HOWEVER...RH VALUES ARE EXPECTED TO REMAIN ABOVE RED FLAG CRITERIA. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 69 84 64 87 60 / 20 30 10 0 0 PANAMA CITY 71 84 69 87 66 / 20 30 10 0 0 DOTHAN 66 83 60 85 58 / 20 30 10 0 0 ALBANY 67 82 61 86 58 / 30 30 10 0 0 VALDOSTA 69 82 63 85 59 / 30 30 10 0 0 CROSS CITY 71 86 63 87 60 / 20 30 10 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT TUESDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM OCHLOCKONEE RIVER TO APALACHICOLA FL OUT TO 20 NM...COASTAL WATERS FROM APALACHICOLA TO DESTIN FL OUT 20 NM...WATERS FROM SUWANNEE RIVER TO APALACHICOLA FL FROM 20 TO 60 NM...WATERS FROM APALACHICOLA TO DESTIN FL FROM 20 TO 60 NM. && $$ JAMSKI/CAMP/BARRY