FXUS62 KTAE 251436
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
936 AM EST WED NOV 25 2009
.DISCUSSION...LONG WAVE PATTERN FEATURES A RIDGE OFF THE E COAST AND
OVER THE PAC NW...AND A TROUGH IN THE MIDDLE OF THE COUNTRY. TWO
SIGNIFICANT SHORT WAVES ARE FOUND WITHIN THE TROUGH. THE ERN MOST
SYSTEM IS PUSHING EWD ACROSS THE OHIO AND TN VALLEYS. AT THE
SURFACE...A COLD FRONT IS PUSHING EWD ACROSS WRN AL THIS MORNING
WHILE A STATIONARY FRONT EXTENDS FROM N FL SWWD TO THE YUCATAN
PENINSULA. WEAK FORCING FOR ASCENT CONTINUES ACROSS THE ERN PORTION
OF THE FORECAST AREA IN THE RIGHT ENTRANCE OF THE UPPER JET AND IN
AN AREA OF WEAK ISENTROPIC LIFT. ALL OF THIS WILL SHIFT EWD THROUGH
THE DAY AND IN FACT WE ARE ALREADY HARD PRESSED TO FIND ANY
MEASURABLE RAIN FALLING FROM THE SKY. WE'LL MONITOR TRENDS THIS
MORNING AND PLAN TO REDUCE POPS IN A LATE MORNING UPDATE IN FAVOR OF
TRACE SPRINKLES. CLOUDS WILL SHIFT EWD AS WELL THROUGH THE REMAINDER
OF THE DAY.
&&
.MARINE...HIGH PRESSURE WILL BEGIN TO BUILD INTO THE COASTAL WATERS
THIS AFTERNOON...CONTINUING INTO THE WEEKEND. MODERATE NLY WINDS
THIS MORNING ARE AT THE LOW END OF CAUTION CRITERIA. WE ARE
EXPECTING A BRIEF DECREASE THIS AFTERNOON...SO WILL HOLD OFF ON THE
HEADLINE. WINDS WILL THEN GRADUALLY INCREASE TONIGHT THROUGH FRIDAY
WITH EXERCISE CAUTION HEADLINES EXPECTED BY EARLY THURSDAY AND
ADVISORY HEADLINES POSSIBLE THURSDAY NIGHT. BY FRIDAY AND
SATURDAY...THE CENTER OF THE HIGH PRESSURE CELL IS FORECAST TO MOVE
OVER THE WATERS WITH WINDS DROPPING BELOW 10 KNOTS.
&&
.AVIATION...WITH COLD FRONT PROGRESSING THROUGH OUR AREA TODAY
BRINGING GRADUALLY CLEARING SKIES. EXPECT VFR CONDITIONS TO REACH
REACH VLD AND ABY BY LATE MORNING. AFTERWORDS... VFR WILL BE THE
RULE THROUGH THURSDAY WITH ONLY HIGH CLOUDS ACROSS THE AREA.
&&
.FIRE WEATHER...MINIMUM AFTERNOON RELATIVE HUMIDITIES MAY DROP BELOW
CRITICAL LEVELS FOR UP TO 4 HOURS OVER PORTIONS OF THE FLORIDA
PANHANDLE ON THU. RED FLAG CONDITIONS LOOK MORE LIKELY OF FRIDAY
FOR ALL OF OUR FLORIDA ZONES DUE TO LOW RELATIVE HUMIDITY. WILL HOLD
OFF ON ISSUING ANY WATCHES AT THIS TIME.
&&
.PREV DISCUSSION...
231 AM EST WED NOV 25 2009
SHORT TERM (TODAY THROUGH FRIDAY)...AMPLIFIED FLOW PATTERN IN PLACE
ACROSS THE CONUS WITH A TROUGH OVER THE CENTRAL PORTION OF THE
COUNTRY AND RIDGES ALONG THE EAST/WEST COASTS. DEEP SOUTHWESTERLY
FLOW OVER THE SOUTHEASTERN STATES IS DRAWING GULF MOISTURE UP AND
OVER A COOL AND STABLE LOW LEVEL AIRMASS OVER NORTH FLORIDA. THE
PRECIP FROM THIS OVERRUNNING IS BEING SOMEWHAT ENHANCED BY A MID
LEVEL SHORTWAVE OVER THE CENTRAL GULF. THE SHORTWAVE WILL MOVE OVER
THE FLORIDA PENINSULA DURING THE DAY TODAY AND THE RAIN OVER THE BIG
BEND WILL COME TO AN END. HOWEVER...THE FORECAST ISSUE IS HOW FAR
WEST THE RAIN SHIELD REACHES BEFORE SHIFTING TO THE EAST. CURRENT
RADAR TRENDS ARGUE POPS BACK TO PANAMA CITY EARLY THIS MORNING AND
WILL HAVE THE GRIDS REFLECT THIS THINKING.
RAIN SHOULD COME TO A QUICK END BY EARLY AFTERNOON AS SHORTWAVE
EXITS. BEHIND THIS SYSTEM...A SHORTWAVE WILL DIVE INTO THE BASE OF
THE CENTRAL U.S. TROUGH...REINFORCING HIGH PRESSURE THAT WILL
BUILD INTO THE DEEP SOUTH THROUGH THE REMAINDER OF THE WEEK. WITH
HIGH PRESSURE BUILDING IN...TEMPS WILL BE ON A GRADUAL DOWNWARD
SWING THROUGH FRIDAY. AFTER HIGHS IN THE UPPER 60S THIS
AFTERNOON...MAX TEMPS WILL STRUGGLE TO REACH THE LOWER 60S BY
FRIDAY. SIMILARLY...LOW TEMPS WILL DROP INTO THE LOWER TO MID 30S
BY FRIDAY MORNING. HAVE GONE SLIGHTLY ABOVE GUIDANCE FOR FRIDAY
MORNING...GIVEN THAT A PRETTY DECENT GRADIENT WILL STILL EXIST
ACROSS THE REGION.
LONG TERM (FRIDAY NIGHT THROUGH WEDNESDAY)...SURFACE HIGH PRESSURE
ASSOCIATED WITH A COOL AND DRY AIR MASS WILL BE CENTERED OVERHEAD
SATURDAY. THIS HIGH WILL MOVE EAST ON SUNDAY AS A VIGOROUS STORM
SYSTEM BEGINS TO ORGANIZE ACROSS THE SOUTHERN PLAINS AND LOWER
MISSISSIPPI VALLEY. BY MONDAY MORNING A DEEP TROUGH IS FORECAST TO
CUT THROUGH THE CENTER OF THE CONUS WITH A CLOSED LOW OVER THE
NORTHERN PLAINS. THE LOW WILL DEEPEN AND DROP ALL THE WAY TO THE
ARKLATEX REGION BY 12Z TUESDAY...SLIDE EAST THROUGH LA AND THEN LIFT
NE TO THE GREAT LAKES BY THE END OF THE FORECAST PERIOD. THE GFS
PLACES THE SURFACE LOW OVER CENTRAL MISSISSIPPI 12Z MONDAY WITH THE
ASSOCIATED COLD FRONT SOUTHWEST THROUGH LA. SHOWERS AD THUNDERSTORMS
AHEAD OF THIS SYSTEM WILL OVERSPREAD OUR AREA MONDAY INTO TUESDAY AS
THE LOW SLOWLY TRANSLATES INTO ALABAMA. THE LOW THEN LIFTS NORTHWARD
THROUGH THE OHIO VALLEY INTO THE GREAT LAKES WEDNESDAY DRAGGING THE
FRONT ACROSS THE TRI-STATE REGION. THE 12Z EURO SOLUTION CONTINUES TO
SHOW A MUCH WEAKER SYSTEM. IF THE GFS VERIFIES...THIS COULD BRING
HEAVY RAINS AND POTENTIALLY SEVERE WEATHER TO OUR REGION DURING THE
MONDAY/MONDAY NIGHT TIME FRAME. WILL TREND POPS UP SLIGHTLY MONDAY
AND TUESDAY BUT KEEP THEM IN THE CHANCE CATEGORY. MINIMUM
TEMPERATURES WILL BE BELOW SEASONAL LEVELS THROUGH THE PERIOD. A
LIGHT FREEZE IS POSSIBLE OVER A PORTION OF OUR CWA SATURDAY MORNING
AS CONDITIONS SET UP FOR IDEAL RADIATIONAL COOLING. MAX TEMPS WILL
GENERALLY RANGE FROM THE MID 60S TO THE LOWER 70S.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 69 43 65 34 62 / 30 0 0 0 0
PANAMA CITY 69 47 65 42 62 / 10 0 0 0 0
DOTHAN 68 39 63 34 60 / 5 0 0 0 0
ALBANY 68 40 64 34 61 / 10 0 0 0 0
VALDOSTA 66 44 66 35 62 / 30 0 0 0 0
CROSS CITY 68 47 69 35 64 / 60 10 0 0 0
APALACHICOLA 69 49 66 43 61 / 30 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
AVIATION...GOREE
PREVIOUS DISCUSSIONS...CAMP/BARRY
REST OF DISCUSSION...WOOL
