000 FXUS62 KTAE 270649 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 150 AM EST FRI NOV 26 2009 .SHORT TERM...TODAY THROUGH SUNDAY....THE UPPER TROUGH ALONG THE EASTERN SEABOARD THIS MORNING WILL MOVE EAST WITH THE UPPER PATTERN GRADUALLY FLATTENING TO BECOME ZONAL BY SUNDAY. DEEP DRY NORTHWEST FLOW TODAY WILL BACK TO THE WEST OVER THE WEEKEND. AT THE SURFACE... HIGH PRESSURE CENTERED OVER EAST TEXAS WILL BUILD EASTWARD ALONG THE GULF COAST TODAY. THE HIGH IS FORECAST TO CENTER OVER OUR CWA BY DAYBREAK SATURDAY. CHILLY TEMPERATURES ACCOMPANY THIS AIR MASS AND WE EXPECT MIN TEMPS TONIGHT TO DROP INTO THE MID 30S AWAY FROM COASTAL AREAS. A FEW OF THE NORMALLY COLDER LOCATIONS COULD BRIEFLY DROP TO THE FREEZING MARK AND AREAS OF FROST ARE STILL POSSIBLE. THE ONLY CONCERN IS THAT WE CAN SEE A THICK CANOPY OF CIRRUS UPSTREAM ALREADY SPREADING ACROSS THE WESTERN GULF. GFS TIME HEIGHT CROSS SECTIONS SHOW THE CIRRUS OVERSPREADING OUR FA LATER TODAY AND OVERNIGHT. THIS WOULD OBVIOUSLY FOIL IDEAL RADIATIONAL COOLING CONDITIONS WITH MIN TEMPS A FEW DEGREES WARMER THAN FORECAST AND MAY HINDER OR LIMIT THE EXTEND OF FROST DEVELOPMENT. WE WILL CONTINUE TO ADVERTISE FROST IN THE GRIDS AND ZONES FOR TONIGHT BUT WILL HOLD OFF ON ISSUING A FROST ADVISORY. ON SUNDAY THE SURFACE HIGH SLIDES FURTHER EAST WITH ANOTHER CHILLY MORNING POSSIBLE OVER THE EASTERN ZONES. MAX TEMPS TODAY AND SATURDAY WILL BE IN THE LOWER TO MID 60S WITH TEMPS RETURNING TO MORE SEASONAL LEVELS ON SUNDAY. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)...GUIDANCE IS IN GOOD AGREEMENT THROUGH MONDAY NIGHT. SPLIT FLOW REGIME WILL BE IN PLACE WITH CUTOFF UPPER LOW OVER NORTHWESTERN MEXICO LAGGING BEHIND THE NORTHERN STREAM TROUGH. THE NORTHERN STREAM TROUGH WILL PUSH A COLD FRONT INTO THE SOUTHEAST STATES STARTING SUNDAY NIGHT. THE FRONT IS FORECAST TO MOVE THROUGH THE FORECAST AREA MONDAY AFTERNOON AND EVENING BEFORE STALLING OVER NORTH CENTRAL FLORIDA TUESDAY. SOUTHWEST FLOW ALOFT WILL LEAD TO OVERRUNNING PRECIP IN THE WAKE OF THE FRONT FOR MONDAY NIGHT INTO TUESDAY. A SIGNIFICANT WAVE IS THEN FORECAST TO DEVELOP ALONG THE FRONT OVER THE GULF OF MEXICO AS THE SOUTHERN STREAM CUT-OFF EJECTS EASTWARD. WHILE THE EURO AND GFS HAS THE SAME GENERAL IDEA...TIMING IS QUITE DIFFERENT WITH THE 27/00Z GFS ABOUT 12-18 HOURS FASTER WITH THE LOW THAN THE 26/12Z ECMWF. REGARDLESS OF THE TIMING...EXPECT TO SEE A BOUT OF HEAVY RAIN AT SOME POINT FROM EARLY TUESDAY TO LATE WEDNESDAY AND WILL BROAD BRUSH THE POPS IN THE GRIDS. GUIDANCE HAS NOT YET SETTLED ON THE TRACK OF THE DEVELOPING SFC LOW. LATEST ROUND OF GUIDANCE TRACKS THE LOW THROUGH THE FLORIDA PANHANDLE WHICH COULD PUT THE BIG BEND BRIEFLY INTO THE WARM SECTOR. IF THIS WERE THE CASE...DYNAMICS WOULD BE MORE THAN FAVORABLE TO SUPPORT SEVERE WEATHER...SO WILL CONTINUE TO CLOSELY MONITOR THE SITUATION. GUIDANCE DOES AGREE THAT SYSTEM SHOULD BE OUT OF THE AREA BY THURSDAY AND FRIDAY WITH DRIER AND COOLER CONDITIONS. && .MARINE...WINDS AND SEAS ARE JUST BELOW SCA LEVELS ACROSS THE LOCAL WATERS EARLY THIS MORNING. WE SHOULD BE ABLE TO LET THE ADVISORY EXPIRE A FEW HOURS EARLY AND REPLACE WITH SCEC HEADLINE. WINDS AND SEAS WILL QUICKLY SUBSIDE TODAY AND TONIGHT AS THE SURFACE HIGH BUILDS OVERHEAD. LIGHT AND VARIABLE CONDITIONS ARE EXPECTED ON SATURDAY WITH AN EAST TO SOUTHEAST FLOW BECOMING ESTABLISHED SUNDAY INTO MONDAY. WINDS AND SEAS ARE EXPECTED TO INCREASE MONDAY NIGHT POSSIBLY REACHING ADVISORY LEVELS ON TUESDAY AS THE NEXT LOW PRESSURE SYSTEM DEVELOPS IN THE WESTERN GULF. && .AVIATION...HIGH PRESSURE WILL BUILD INTO THE AREA TODAY BRINGING LIGHT NORTHWESTERLY WINDS AND MOSTLY CLEAR SKIES. VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD AT ALL TERMINALS. && .FIRE WEATHER...DRY AIR MASS IN PLACE TODAY WILL ALLOW RH TO DROP BELOW 35 PERCENT FOR AROUND 4 HOURS FOR ALL INLAND AREAS OF THE FLORIDA ZONES...SO WILL CONTINUE THE RED FLAG WARNING. SIMILAR CONDITIONS EXPECTED FOR SATURDAY WITH DURATIONS RIGHT AROUND 4 HOURS. WILL KEEP THE WATCH UP FOR ALL BUT GULF AND FRANKLIN COUNTIES FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 62 34 63 34 70/ 00 00 00 00 00 PANAMA CITY 61 41 66 46 71/ 00 00 00 00 00 DOTHAN 60 36 63 42 70/ 00 00 00 00 00 ALBANY 61 34 64 38 70/ 00 00 00 00 00 VALDOSTA 60 35 64 36 71/ 00 00 00 00 00 CROSS CITY 62 34 63 34 74/ 00 00 00 00 00 APALACHICOLA 61 38 63 40 69/ 00 00 00 00 00 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...RED FLAG WARNING 18-23Z TODAY ALL ZONES. FIRE WEATHER WATCH SATURDAY AFTERNOON ALL BUT GULF AND FRANKLIN COUNTIES. GM...NONE. && $$ BARRY/CAMP