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000 FXUS62 KTAE 120719 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 245 AM EDT SUN OCT 12 2008 .SYNOPSIS... AT 2 AM EDT...IT WAS MOSTLY CLOUDY TO CLOUDY ACROSS LOCAL AREA WITH STRATUS CIGS 1-2K. TEMPS WERE GENERALLY AROUND 70F. 24 HR TEMP/DEW POINT COMPARISON INDICATES LITTLE AIRMASS CHANGE SINCE SAME TIME YESTERDAY. WINDS NE 5-10 MPH WITH LOCALLY HIGHER GUSTS...THIS PREVENTING FOG FROM DEVELOPING. AT UPPER LEVELS... CONUS PATTERN HIGHLIGHTED BY AN AMPLIFIED RIDGE OVER ERN MOST PACIFIC...A DEEP AMPLITUDE TROUGH CENTERED OVER THE INTERMTN WEST WITH INTENSE LOW OVER GREAT BASIN...AND A HIGH AMPLITUDE RIDGE AXIS FROM THE ERN GREAT LAKES TO OH RIVER VALLEY AND THE NRN GOMEX. IN BETWEEN THESE SYSTEMS...A MOISTURE PLUME FROM HURRICANE NORBERT STREAMING NEWD INTO THE PLAINS. CLOSER TO HOME, A WEAK H5 LOW WAS CENTERED NEAR THE SE GA COAST. DRIER AIR ALOFT WAS FILTERING SWD ACROSS THE TRI-STATE REGION ON THE WRN PERIPHERY OF THIS CIRCULATION. TROUGH WILL AMPLIFY EAST SOME TODAY WITH DEEP LAYER RIDGE BUILDING OVER THE NE CONUS TODAY WILL TRAP THIS LOW AND SFC TROUGH OFF THE NE FLORIDA COAST (SEE BELOW) FORCING THEM UNDERNEATH THE RIDGE AND SHUNTED WSW. LOW WILL WEAKEN AS IT RETROGRADES SLOWLY ACROSS N FL TODAY (WITH CWA ON WEAK PVA SIDE OF LOW)...THE ERN GULF TONIGHT AND INTO THE WRN GULF ON MONDAY LEAVING DRIER AIR IN ITS PLACE. BY TUESDAY...CONUS PATTERN DEAMPLIFIES WITH TROUGH SHIFTING EWD INTO CNTRL CONUS NUDGING INTO ERN RIDGE WITH SUBSEQUENT WEAKENING OF LATTER SYSTEM. AT LOWER LEVELS... DURING PREDAWN HOURS...LARGE CANADIAN SFC HIGH LOCATED ACROSS NEW ENGLAND WILL CONTINUE TO SHIFT SLOWLY SE UNDER THE UPPER RIDGE. DURING REST OF TODAY...SURFACE HIGH PRESSURE WILL DROP INTO MID-ATLANTIC AND STRENGTHEN WITH RIDGING SWWD INTO SE CONUS. SECOND FEATURE OF NOTE IS AN INVERTED TROUGH JUST EAST OF THE ABOVE H5 LOW. AS HIGH DROPS FURTHER SWD AND TROUGH MOVES WWD TO COAST...A FAVORABLE WEDGE SETUP DEVELOPS FOR THE SE U.S. THIS IN COMBINATION WITH WWD DRIFTING H5 LOW WILL MAINTAIN MODERATE TO BREEZY EAST TO NORTHEAST WINDS THROUGH TUESDAY...BRINGING ATLANTIC MOISTURE INTO THE REGION. .SHORT TERM (TODAY THROUGH TUESDAY)... INCREASING LOW LEVEL GRADIENT AND ASSOCIATED SFC CONVERGENCE WILL GENERATE SCATTERED LIGHT SHOWERS/SPRINKLES OVER THE MAINLY ERN HALF OF THE CWA TODAY UNTIL THE UPPER LOW/TROUGH MOVES OVER CWA. BY TONIGHT...THEY WEAKEN FURTHER AND MOVE WEST OF CWA AND WASH OUT WITH DRY MID-UPPER AIR FILTERING IN. UNTIL THEN..EXPECT GUSTY EAST WINDS. HOWEVER...LOWER LEVEL MOISTURE LINGERS UNTIL LATE MON-EARLY TUES. THIS REFLECTED IN AREA MODEL SOUNDINGS. I.E. GFS TAE WITH 1.40 PWAT AT 12Z SUN UP TO 1.84 PWAT AT 06Z MON AND THEN DROPPING TO 1.07 PWAT AT 12Z TUES. TEMPERATURES WILL REMAIN SEASONABLE THROUGH THE SHORT TERM WITH PLENTY OF LOW CLOUD COVER. SREF INDICATES THAT LOW STRATUS WILL DOMINATE CWA THIS MORNING...LESS SO MONDAY MORNING BUT THAT FOG FORMATION AT NIGHT SHOULD BE LIMITED BY SUFFICIENT BOUNDARY LAYER WINDS AND CLOUD COVER. TODAY...00Z AREA SOUNDINGS INDICATE THAT MOST OF THE MOISTURE WAS CONFINED TO THE LOW LEVELS (BELOW 700 MB) DUE TO MODERATE E-NE FLOW. THUS...LOW CLOUDS ALONG WITH SCT LIGHT SHOWERS AND ISOLD TSTMS WITH LOCAL GUSTS WILL CONTINUE TO SPREAD WEST AND THEN SOUTH AND COVER MUCH OF THE AREA. 20-50 PCT SW-NE POP GRADIENT. INLAND HIGHS FROM NEAR 80 SE ALA/SW GA TO MID 80S SE BIG BEND. LOWS TONIGHT MID-UPPER 60S. MONDAY...20 PCT LIGHT RAIN ACROSS CWA. LOCALLY BREEZY AND GUSTY. INLAND HIGHS IN LOW-MID 80S. TUESDAY...NO POPS. INLAND HIGHS IN THE MID 80S. .LONG TERM (WEDNESDAY THROUGH SUNDAY)...BETTER AGREEMENT THIS RUN BETWEEN THE GFS AND 12 UTC ECMWF. BOTH MODELS SHOW DEEP LAYER RIDGING AND A VERY DRY AIRMASS IN PLACE ON WEDNESDAY. THE FLOW BECOMES ZONAL THURSDAY AS A TROUGH DEVELOPS AND DEEPENS OVER THE PLAINS. THE TROUGH CONTINUES TO AMPLIFY AS IT MAKES ITS WAY TOWARD THE EASTERN U.S. 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 SHOWING A MOISTURE STARVED FRONTAL PASSAGE FRIDAY NIGHT/EARLY SATURDAY. BOTH MODELS THEN SHOW HIGH PRESSURE AND A COOLER DRIER AIRMASS 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 WITH MORE SEASONAL TEMPS NEXT WEEKEND. && .AVIATION...AS OF 06Z...MVFR CIGS HAVE BLANKETED THE REGION. SO FAR VSBYS HAVE STAYED UP AS THE WINDS CONTINUE AROUND 10 KTS. HAVE ACCOUNTED FOR THE POSSIBILITY OF IFR CIGS AND MVFR VSBYS UNTIL JUST AFTER DAYBREAK. THEN...CONDITIONS WILL GRADUALLY IMPROVE AFTER 15Z WITH ALL SITES LIKELY VFR BY 18Z. WINDS WILL ONCE AGAIN BE LOCALLY GUSTY UP TO 18KT THIS AFTERNOON. WENT WITH PROB30 GROUPS FOR LIGHT RAIN THIS EVENING AT ABY AND VLD. && .MARINE... LATEST OBS INDICATE NELY WINDS 10-15 KTS/2-4 FT SEAS NEAR SHORE AND 15-20 KTS/3-5 FT SEAS OFFSHORE...LITTLE CHANGE SINCE SAT EVENING. EXPECT BOTH TO SLOWLY INCREASE OVER THE COASTAL WATERS AS STRONG HIGH PRESSURE BUILDS DOWN THE EASTERN SEABOARD. SHORT RANGE MODEL PROGS SUGGEST THESE CONDITIONS WILL PERSIST OFFSHORE TODAY, WITH EXERCISE CAUTION HEADLINES AND THEN INCREASE BY TONIGHT TO SCA LEVELS INTO MONDAY AND PEAKING ON MONDAY NIGHT. WINDS AND SEA WILL THEN SLOWLY DECREASE BEGINNING ON TUESDAY. NEXT SHIFT WILL LIKELY HAVE TO INTRODUCE SCA INTO CWF. && .FIRE WEATHER...NO FIRE WEATHER CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 82 68 84 65 / 30 20 20 10 PANAMA CITY 82 71 83 69 / 20 20 20 10 DOTHAN 77 65 82 62 / 30 20 20 10 ALBANY 77 67 82 62 / 40 30 20 10 VALDOSTA 80 68 82 64 / 40 20 20 10 CROSS CITY 85 68 85 64 / 30 20 20 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...NONE. && $$ CAMP/WATSON/BARRY