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000 FXUS62 KTAE 040808 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 230 AM EST TUE NOV 4 2008 ...VOTERS HEADING TO THE POLLS WILL ENJOY PLEASANT WEATHER... .SYNOPSIS... AT 2 AM EDT...11-3.9 MICRON SATELLITE IMAGERY SHOWS THAT LOW CEILINGS (AOB 1K) HAVE SPREAD SOUTHWEST TO COVER BUT WRN PANHANDLE COAST. TEMPERATURES RANGED FROM UPPER 50S NORTH TO LOW 60S SOUTH. 24 HR TEMP/DEW POINT COMPARISON INDICATES THAT THE LOCAL AIRMASS CONTINUES TO BE WARMER AND MOISTER THAN SAME TIME YESTERDAY. WINDS WERE GENERALLY NE 5 TO 10 MPH. AT UPPER LEVELS.. LOOKING AT THE BIG PICTURE...PROGRESSIVE UPPER TROUGH ALONG WEST COAST OVERNIGHT WILL SHIFT EWD AND AMPLIFY ACROSS INTERMOUNTAIN REGION TODAY AND ROCKIES TONIGHT BEFORE BECOMING NEGATIVELY TILTED OVER THE PLAINS ON WED. IN RESPONSE...DOWNSTREAM UPPER RIDGING WILL MOVE OVER THE MISS RIVER VALLEY TODAY AND TOWARDS THE EAST COAST ON WED. LIKEWISE...DEEPENING TROUGH OVER ERN CONUS TODAY WILL LIFT NE AND AWAY FROM CWA. CLOSER TO HOME...SATELLITE AND UPPER AIR DATA AT 06 UTC SHOW THE UPPER LOW (WITHIN ERN TROUGH) OVER THE CAROLINAS INTO THE OH VALLEY WITH DRIER MID LEVEL AIR PULLING IN FROM THE WEST AS INDICATED ON THE 00 UTC SOUNDING AT KTAE WITH DRYING NOTED ABOVE 650 MB. AS THE UPPER LOW CONTINUES TO PULL AWAY...MORE DRIER AIR WILL CONTINUE TO WORK SW-NE AND INTO THE REGION. THIS LOW IS ROTATING SLOWLY N AND MODELS IN GOOD AGREEMENT THAT IT WILL GRADUALLY LIFT FURTHER N TODAY AND PHASE WITH UPPER LEVEL TROUGH AND A SHORT WAVE CURRENTLY MOVING THROUGH THE GREAT LAKES. IN ITS PLACE...A RIDGE WILL MOVE OVER THE AREA FOR A FEW DAYS BEFORE THE NEXT WEATHER MAKER...A DEEP UPPER LOW MOVING ACROSS FROM THE MIDWEST INTO THE MISSISSIPPI VALLEY BEGINS TO IMPACT ERN CONUS. (SEE LONG TERM DISCUSSION). THIS IS REFLECTED IN REGIONAL 00Z MODEL SOUNDINGS. I.E. GFS TAE WITH 1 INCH PWAT AT 00Z TUES DOWN TO 0.38 INCH AT 12Z FRI BEFORE RAPIDLY INCREASING TO 1.37 INCH AT 06Z SAT. AT LOWER LEVELS... ANALYSIS SHOWS A LARGE INVERTED LOW PRESSURE TROUGH OVER THE BAHAMAS EXTENDING NW AND UP THE EASTERN SEA BOARD INTO THE CAROLINAS WITH A LOW JUST OFF NC//SC COAST. JUST UPSTREAM...HIGH PRESSURE PERSISTS FROM THE MID ATLANTIC DOWN INTO THE GULF COAST. SURFACE RIDGING EXISTS FROM THE OHIO RIVER VALLEY SOUTHWARD AROUND THE WEST SIDE OF THIS LOW AND INTO THE CNTRL GULF. THE COMBINATION OF ABOVE HAS CREATED A MOIST LOW LEVEL NORTHEAST FLOW ACROSS OUR REGION. AS LOW LIFTS FURTHER NWD AND AWAY FROM CWA TODAY...LOCAL GRADIENTS WILL CONTINUE TO WEAKEN. WEAK HIGH PRESSURE AT ALL LEVELS WILL BEGIN TO BUILD INTO AREA AS THE SURFACE RIDGE SHIFTS EWD TO THE EAST GULF AND CWA BY WED. THIS WILL SCOUR OUT RECENT LOW CLOUDS AND YIELD MOSTLY CLEAR SKIES AND MODERATING TEMPERATURES BEGINNING THIS AFTERNOON AND CONTINUING THRU THE SHORT TERM PERIOD. THE NEXT WEATHER MAKER WILL BE A COLD FRONT LIKELY PASSING THRU ON FRIDAY (SEE LONG TERM DISCUSSION). && .SHORT TERM (TODAY THROUGH THURSDAY)... SHORT TERM MARKED BY NO POPS AND SLOWLY WARMING TEMPERATURES. TODAY...DURING THIS MORNING...NORTHEAST FLOW WEST OF THE ABOVE LOW WILL CONTINUE TO PUSH LOW CLOUD DECK ACROSS CWA...ESPECIALLY THICK OVER THE EASTERN HALF. THESE CLOUDS ARE EXPECTED TO LINGER BEFORE BURNING OFF BY AFTERNOON. INLAND HIGHS FROM LOW 70S EAST TO MID 70S ELSEWHERE. WEDNESDAY...WITH DECREASING LOW CLOUDS...INLAND HIGHS IN UPPER 70S. THURSDAY...UNDER SUNNY SKIES AND VEERING WINDS...INLAND HIGHS AROUND 80. .LONG TERM...FRIDAY THROUGH TUESDAY...THE AXIS OF A DEEPENING UPPER TROUGH WILL SWING ACROSS THE REGION FRIDAY THROUGH SATURDAY. AS THE TROUGH MOVES OFF THE EAST COAST...THE FLOW BECOMES ZONAL ON SUNDAY AND THEN BACKS TO THE SOUTHWEST MONDAY AS THE NEXT SHORTWAVE MOVES INTO THE LOWER MISSISSIPPI VALLEY. THIS SHORTWAVE IS FORECAST TO DAMPEN OUT AS THE ENERGY MOVES INTO THE MID ATLANTIC STATES TUESDAY MAINTAINING SOUTHWEST FLOW OVER THE SOUTHEAST CORNER OF THE U.S. AT THE SURFACE...A COLD FRONT WILL PUSH FROM WEST TO EAST ACROSS OUR CWA FRIDAY AFTERNOON THROUGH FRIDAY NIGHT. THE FRONT WILL BE WEAKENING AND DUE TO ITS LATE TIMING...LOCATIONS LUCKY ENOUGH TO RECEIVE RAIN MAY AT BEST GET ONE-TENTH OF AN INCH. WILL KEEP POPS IN THE MID RANGE CHANCE CATEGORY WHICH IS ALSO SUPPORTED BY GFSX MOS GUIDANCE. THE WEEKEND INTO MONDAY WILL BE DRY WITH MIN TEMPS COOLING GENERALLY INTO THE LOWER TO MID 40S FOR INLAND LOCATIONS. MAX TEMPS WILL UNDER FULL SUN SHOULD CONTINUE AT OR JUST ABOVE SEASONAL LEVELS. ANOTHER COLD FRONT ASSOCIATED WITH THE AFOREMENTIONED SECOND SHORTWAVE WILL BRING ANOTHER CHANCE OF RAIN LATE TUESDAY. && .AVIATION...STRATUS LATER SPREADING RAPIDLY FROM EAST TO WEST ACROSS THE REGION. EXPECT WIDESPREAD IFR CIGS AND POSSIBLY MVFR VSBYS THROUGH SUNRISE. ANY VSBY RESTRICTIONS WILL BE BRIEF DUE TO THE WINDS REMAINING IN THE 5 TO 10 KT RANGE WITH HIGHER GUSTS. CIGS WILL GRADUALLY ELEVATE TO MVFR AND THEN VFR BUT OUR EASTERN SITES (ABY AND VLD) MAY NOT SEE VFR CONDITIONS UNTIL EARLY TO MID AFTERNOON. SKIES SHOULD CLEAR AT ALL TAF SITES BY THE END OF THE FORECAST PERIOD. && .MARINE...THE PRESSURE GRADIENT WILL CONTINUE TO LOOSEN AS THE SURFACE TROF...AND EVENTUALLY SURFACE LOW...MOVES UP THE EAST COAST AND HIGH PRESSURE NUDGES DOWN THE TENNESSEE VALLEY TOWARD OUR WATERS. THIS WILL RESULT IN GRADUALLY DECREASING WINDS AND LOWERING SEAS OVER THE NEXT 36 HOURS. BY LATE TONIGHT THROUGH THURSDAY...WINDS AND SEAS WILL BE MINIMAL AS HIGH PRESSURE SETTLES IN OVER THE WATERS. WINDS AND SEAS WILL INCREASE FRIDAY AS THE NEXT FRONTAL SYSTEM APPROACHES THE WATERS. && .FIRE WEATHER...DRIER AIR WILL FILTER INTO THE REGION THE NEXT FEW DAYS. MINIMUM RH VALUES THIS AFTN WILL REMAIN ABOVE CRITICAL THRESHOLDS, AND MAY APPROACH THE FL CRITERIA (SUB-35 PERCENT) WED AFTN BUT DURATIONS ARE NOT EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 76 50 79 46 / 0 0 0 0 PANAMA CITY 74 56 78 57 / 0 0 0 0 DOTHAN 74 50 78 49 / 0 0 0 0 ALBANY 74 49 78 48 / 0 0 0 0 VALDOSTA 72 50 77 48 / 0 0 0 0 CROSS CITY 75 50 78 48 / 0 0 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...NONE. && $$ BLOCK/BARRY