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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCAE 100202
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
902 PM EST TUE FEB 9 2010

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH TONIGHT. AN AREA OF LOW PRESSURE WILL
DEVELOP TO OUR NORTHEAST TONIGHT AND WEDNESDAY...AND LEAD TO WINDY
CONDITIONS WEDNESDAY. AN AREA OF LOW PRESSURE WILL RIDE BY TO OUR
SOUTH FRIDAY AND FRIDAY NIGHT AND LEAD TO A SLIGHT CHANCE OF
PRECIPITATION.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
-- Changed Discussion --
UPDATE AS OF 900 PM: COLD FRONT NOW BEGINNING TO PUSH THROUGH
CENTRAL MIDLANDS. EXPECT WIND SPEEDS TO INCREASE IN WAKE OF FRONT
DURING THE OVERNIGHT HOURS. WILL CONTINUE SMALL CHANCE FOR RAIN
UNTIL MIDNIGHT ACROSS THE AREA AS PER LATEST RADAR TRENDS.

PREVIOUS DISCUSSION: CURRENT SURFACE ANALYSIS INDICATES A COLD
FRONT TO OUR WEST NEAR ALA/GA...WITH A PAIR OF WEAK LOW PRESSURE
AREAS ON THEM. A WEAK WEDGE IS IN PLACE OVER OUR FA. WILL EXPECT
PERIODS OF LIGHT RAIN THROUGH THIS AFTERNOON...UNTIL THE COLD
FRONT AND UPPER LEVEL DISTURBANCE MOVE THROUGH EARLY THIS EVENING.
THE LOW PRESSURE AREAS WILL DEVELOP AS THEY SHIFT OFF TO OUR NE.
THE PRESSURE GRADIENT WILL INCREASE OVER OUR REGION BETWEEN THE
LOWS TO OUR NE AND HIGH PRESSURE DIVING INTO THE PLAINS TONIGHT.
WILL EXPECT BREEZY CONDITIONS TO DEVELOP TONIGHT BEHIND THE COLD
FRONT. WILL PUSH BACK THE START OF THE LAKE WIND ADVISORY SLIGHTLY
TO 10PM.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
AREA OF LOW PRESSURE TO OUR NE WILL DEVELOP RAPIDLY...AND LEAD TO
WINDY CONDITIONS DEVELOPING OVER OUR FA WEDNESDAY.  IT APPEARS THAT
SUSTAINED WINDS ABOVE 30 MPH...WITH FREQUENT GUSTS OF 40 MPH OR
HIGHER WILL BE EXPECTED. WILL UPGRADE TO A GENERAL WIND ADVISORY.
WILL EXPECT SOME DIMINISHING WIND SPEEDS WED NIGHT..BUT WINDS ON
AREA LAKES COULD STILL BE HIGH ENOUGH FOR A LAKE WIND ADVISORY WED
NT. HOWEVER...MULTIPLE HEADLINES COULD GET CONFUSING. A CONTINUED
INFLUX OF DRY AND COOL AIR EXPECTED THURSDAY WITH LESS WIND.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
CLOSED LOW CURRENTLY OFF THE CA COAST WILL OPEN AND SHIFT ESE.
LATEST GFS OPENS THE UPPER LOW AND TAKES IT ES ACROSS THE GULF OF
MEXICO AND FLORIDA FRI/FRI NT...TAKING THE CORRESPONDING SURFACE LOW
WELL SOUTH ACROSS THE FLORIDA STRAITS...KEEPING ASSOCIATED MOISTURE
WELL TO OUR SOUTH. CANADIAN AND ECMWF SUGGEST THE LOW COULD BE
SLIGHTLY FARTHER NORTH. DON`T SEE ANY REASON AT THIS TIME TO ALTER
THE ONGOING FORECAST OF A SLIGHT CHANCE OF RAIN OR SNOW FRI/FRI NT
TIME FRAME. REST OF THE EXTENDED RANGE LEFT UNCHANGED. MODELS
DEVELOP A DRY AND COOL NW FLOW ALOFT. SOME UPPER ENERGY AND A
SURFACE BOUNDARY MAY AFFECT US EARLY NEXT WEEK...BUT MOISTURE
APPEARS LIMITED AT THIS TIME.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
A COLD FRONT WILL PASS THROUGH THE REGION 00Z-04Z TIME FRAME EARLY
IN THE PERIOD. MAINLY VFR CONDITIONS BUT MVFR CONDITIONS ARE
POSSIBLE ALONG AND AHEAD OF THE FRONT. AFTER THE FRONT MOVES EAST...
A STRONG PRESSURE GRADIENT DEVELOPS AND WINDS INCREASE TO WEST
10-20 KNOTS 00Z-10Z THEN INCREASE TO WEST 20-30 KNOTS AND GUSTY
FOR WEDNESDAY. OCCASIONAL MODERATE LOW LEVEL TURBULENCE BUT WIND
SHEAR NOT EXPECTED TO BE SIGNIFICANT FACTOR...JUST SPEED SHEAR BUT
SHEAR MAGNITUDE 20 KNOTS OR LESS.

EXTENDED AVIATION OUTLOOK...WINDS WILL DIMINISH WEDNESDAY NIGHT.
CEILING AND VISIBILITY RESTRICTIONS ALSO POSSIBLE FRIDAY INTO
SATURDAY AS ANOTHER LOW PRESSURE SYSTEM PASSES TO OUR SOUTH.

&&

.FIRE WEATHER...
DUE TO A SIGNIFICANT INCREASE IN WIND SPEED ALONG WITH LOW RELATIVE
HUMIDITIES NEAR OR BELOW 25 PERCENT EXPECTED WED AFTN...THE
METEOROLOGICAL CRITERIA FOR A RED FLAG WARNING OR FIRE WEATHER
WATCH COULD BE MET. HOWEVER...FUEL MOISTURE VALUES ARE HIGH DUE TO
RECENT RAINS. COORDINATED WITH FEDERAL AND STATE FIRE WEATHER
OFFICIALS...AND THEY CONFIRMED FUEL MOISTURE VALUES ARE VERY HIGH
AND A RED FLAG WARNING OR FIRE WEATHER IS NOT NEEDED.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
SC...LAKE WIND ADVISORY UNTIL 9 AM EST WEDNESDAY FOR SCZ015-016-018-
     020>022-025>031-035>038-041.
     WIND ADVISORY FROM 9 AM TO 7 PM EST WEDNESDAY FOR SCZ015-016-
     018-020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY UNTIL 9 AM EST WEDNESDAY FOR GAZ040-063>065-
     077.
     WIND ADVISORY FROM 9 AM TO 7 PM EST WEDNESDAY FOR GAZ040-
     063>065-077.
-- End Changed Discussion --

&&

$$