FXUS62 KFFC 041535 AAB
AFDFFC
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1035 AM EST FRI DEC 4 2009
.UPDATE...
MOISTURE FROM THE GULF BEGINNING TO MOVE INTO CENTRAL GEORGIA A
LITTLE FASTER THAN EXPECTED...LEADING TO INCREASED CLOUD COVER.
HAVE ADJUSTED SKY GRIDS AS WELL AS POPS...ONLY PUT A SLIGHT CHANCE
EXTREME (AND I DO MEAN EXTREME) SOUTHEAST...BUT INCREASED SOME
OTHER AREAS TO 10-14%. ALSO LOWERED MAX TEMPS IN SOUTHEAST ZONES
TO ACCOUNT FOR THE CLOUD COVER. NEW NAM IS INDICATING THE
POSSIBILITY OF SLIGHTLY HIGHER SNOWFALL AMOUNTS FOR TONIGHT INTO
TOMORROW...BUT WILL LEAVE FORECAST AS IS SINCE THE REST OF THE 12Z
MODELS ARE NOT YET IN. ZONES WILL BE OUT SHORTLY.
TDP
&&
.PREV DISCUSSION... /ISSUED 448 AM EST FRI DEC 4 2009/
..SNOW ACCUMULATIONS POSSIBLE IN PORTIONS OF NORTH GEORGIA EARLY
SATURDAY MORNING...
SHORT TERM /TODAY THROUGH SUNDAY/...
A SHORTWAVE TROUGH NOW DIPPING INTO SOUTHERN NEW MEXICO WILL RACE
EASTWARD TODAY ACROSS THE SOUTHERN STATES REACHING GEORGIA
SATURDAY MORNING. SURFACE LOW PRESSURE DEVELOPING OVER THE GULF OF
MEXICO IN RESPONSE TO THIS APPROACHING TROUGH WILL SPREAD
PRECIPITATION ACROSS SRN AL/FL/GA AND THE CAROLINAS TONIGHT AND
SATURDAY. COLD ADVECTION OCCURRING THROUGHOUT THE DAY TODAY AND
TONIGHT WILL BRING H8 TEMPS DOWN TO ZERO-MINUS 4 DEG C BY SATURDAY
MORNING OVER MUCH OF NORTH GEORGIA...NORTHWEST OF INTERSTATE
85...WHERE FORECAST SOUNDINGS SUGGEST A MIX OF RAIN AND SNOW IS
POSSIBLE AFTER MIDNIGHT TONIGHT THROUGH SATURDAY MORNING. THE
PRECIPITATION TYPE SHOULD BE PREDOMINANTLY SNOW OVER THE NORTH
GEORGIA MOUNTAINS WHERE TEMPERATURES (SURFACE&ALOFT) SHOULD BE
COLD TO ENOUGH TO ALLOW SOME ACCUMULATIONS. SHORT TERM
MODELS/ENSEMBLES ARE INCONSISTENT WITH THEIR HANDLING OF THIS
EVENT LEADING TO REDUCED CERTAINTY IN EXACT SNOW AMOUNTS...WITH
THE NAM/WRF WETTEST AND THE SREF DRIEST. CONSENSUS POINTING TOWARD
AN INCH OR TWO OF SNOW ACCUMULATION IN HIGHER ELEVATION MOUNTAIN
LOCATIONS AND GENERALLY LESS THAN A HALF INCH NORTH OF A FRANKLIN
TO MARIETTA TO CLEVELAND LINE. THE LIGHT SNOW MAY LINGER INTO
EARLY SATURDAY AFTERNOON OVER THE NORTHEAST GEORGIA MOUNTAINS.
HIGH PRESSURE BUILDING IN FROM THE WEST LATE SATURDAY WILL ALLOW
SKIES TO CLEAR AND WINDS TO DROP OFF...BRINGING OPTIMAL
RADIATIONAL COOLING SATURDAY NIGHT. THE HIGH WILL SLIDE EAST OF
GEORGIA ON SUNDAY.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE UPPER LEVEL PATTERN BECOMES MORE ZONAL ACROSS THE EASTERN U.S.
EARLY NEXT WEEK ALLOWING A FEW WEAK SYSTEMS TO PUSH THROUGH THE
LOCAL AREA WITH OUR AIRMASS GRADUALLY WARMING AND MOISTENING. AN
UPPER TROUGH DIGGING INTO THE WESTERN STATES ON MONDAY/TUESDAY WILL
SPAWN A POWERFUL ~970 MB SURFACE LOW WHICH TRACKS FROM THE CENTRAL
PLAINS TO THE GREAT LAKES BY WEDNESDAY...AS AN ASSOCIATED COLD
FRONT SURGES THROUGH GEORGIA. PRIOR TO THAT FRONTAL PASSAGE
THOUGH...APPEARS TO BE A RATHER EXTENDED PERIOD OF RAIN /POSSIBLY
HEAVY/ TUESDAY INTO WEDNESDAY.
RRH
AVIATION...
DECEASING CLOUDS THIS MORNING WITH INCREASING CLOUDS EXPECTED LATE
TONIGHT INTO SATURDAY WITH NEXT WEATHER SYSTEM MOVING IN. LOW
CEILINGS SLOWLY DISSIPATING THIS MORNING ACROSS N GA ALLOWING THE
ATL AREA TAF SITES TO SCT/CLR OUT. CONDITIONS SHOULD STAY VFR
THROUGH THE DAY WITH WINDS CONTINUING OUT OF THE NW AT 5 TO 10 KTS.
NO RESTRICTIONS TO VSBYS OF PRECIP EXPECTED UNTIL AFTER 00Z SAT.
CEILINGS WILL START TO COME BACK DOWN WITH RAIN MOVING IN AFTER 00Z
SAT. VSBYS SHOULD STAY 5SM OR BETTER WITH CEILINGS GETTING INTO THE
MVFR RANGE. WINDS SHOULD STAY OUT OF THE NW AT 5 TO 10 KTS WITH SOME
HIGHER GUST IN THE STRONGER STORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 52 39 44 29 55 / 5 70 50 5 5
ATLANTA 49 37 42 30 53 / 5 60 50 5 5
BLAIRSVILLE 46 33 37 23 49 / 10 60 80 5 5
CARTERSVILLE 48 33 41 25 52 / 5 60 50 5 5
COLUMBUS 53 40 47 30 56 / 5 70 40 5 5
GAINESVILLE 48 38 41 29 53 / 5 70 60 5 5
MACON 54 39 47 28 58 / 10 70 40 5 5
ROME 49 34 40 25 53 / 0 60 50 5 5
PEACHTREE CITY 50 35 43 24 53 / 5 60 40 5 5
VIDALIA 57 42 51 30 59 / 10 70 40 5 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
