FXUS62 KFFC 291011 AAA
AFDFFC
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
512 AM EST SUN NOV 29 2009
.SHORT TERM /TODAY THROUGH TUESDAY/...
ONE MORE NICE DAY BEFORE A RAINY MONDAY MORNING GREETS NORTH
GEORGIA COMMUTERS. SHORT WAVE WITH ASSOCIATED FRONT AND UVV STILL
ON TRACK TO MOVE THROUGH THE REGION ON MONDAY BASED ON 00Z MODELS.
MODELS CONTINUING TREND TO PUSH UPPER TROUGH AXIS AND UVV THROUGH
QUICKLY WITH LIMITED VERTICAL MOTION MONDAY AFTERNOON. FCST GRIDS
SHOW DRAMATIC DECREASE IN POPS MON AFTERNOON BUT NOT AS MUCH AS
MAV AND MET GUIDANCE. MEAN TROUGH PUSHES OFF THE EAST COAST TUES
AS ATTENTION SHIFTS TO MORE SIGNIFICANT SOUTHERN STREAM SYSTEM
PROGGED TO MOVE ACROSS THE GULF COAST STATES AND INTO GEORGIA ON
WED AND WED NIGHT. IN BETWEEN THESE TWO SYSTEMS...SHOULD SEE DRY
AND COOL CONDITIONS. BLEND OF MAV/MET GUIDANCE GENERALLY USED.
BIAS ADJUSTMENT LESS HELPFUL DURING RAINY/CLOUDY PERIODS.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
WITH EACH RUN OF THE GFS AND ECMWF...UPPER LOW PROGGED TO LIFT OUT
OVER THE STATE WED NIGHT APPEARS STRONGER AND MORE INTENSE. FCSTS
VALID 00Z THU SHOW SFC PRESSURE OVER THE STATE NOW DOWN TO 996MB
ON BOTH 00Z GFS AND 00Z ECMWF. VERY STRONG WARM/MOIST ADVECTION
AHEAD OF SYSTEM SHOULD PRODUCE WIDESPREAD RAIN EVENT ON TUES NIGHT
AND WED MORNING. STRONG CONVECTION ALSO POSSIBLE WED AFTERNOON
JUST SOUTH AND EAST OF SFC LOW TRACK WHERE GFS MUCAPE NOW AROUND
500 J/KG. TREMENDOUS LOW AND MID LEVEL SHEAR IN PLACE IN WARM
SECTOR...50KTS 0-1KM AND 70-80KTS 0-6KM BULK SHEAR MAGNITUDES OVER
AREAS EAST OF KMCN 18Z WED. WITH SUFFICIENT LOW LEVEL BASED
INSTABILITY...WOULD LIKELY SEE SVR STORMS WITH DAMAGING WINDS AND
ISOLD TORNADOES POSSIBLE. TOO SOON TO ADVERTISE ANY OF THIS IN
HWO BUT SOME CONSISTENCY HAS BEEN ESTABLISHED OVER THE LAST TWO
DAYS WORTH OF MODEL RUNS. HOPEFULLY AIRMASS IN PLACE BEFORE ONSET
OF PRECIP WILL BE DRYER AND COOLER THAN PROGGED /WHICH OFTEN
OCCURS/...KEEPING MOST OF CWA STABLE THROUGHOUT THE EVENT. FOR NOW
HAVE GONE WITH STRONGER WINDS AND PERIODS OF HVY RAIN IN FCST
GRIDS. USED MEX GUIDANCE FOR TEMPS WITH INCREASED GRADIENTS
ACROSS BAROCLINIC ZONES AS MOS DOES POORLY WITH THIS IN STRONG
SYSTEMS. LATER SHIFTS WILL NEED TO CONTINUE THIS ADJUSTMENT WITH
FUTURE FCST PACKAGES.
BEYOND THIS...WEATHER SHOULD BE FAIRLY BENIGN. COULD SEE ANOTHER
RAIN EVENT LATE SAT OR SUN BASED ON 00Z GFS BUT 00Z ECMWF IS
HAVING NONE OF THAT. ADDED SLT CHC SHRA TO SUN GRIDS WHICH GET
PUBLISHED IN THE AFTERNOON PACKAGE.
SNELSON
&&
.AVIATION...
VFR CONDITIONS WILL PERSIST THROUGH 12Z TOMORROW AS HIGH PRESSURE
BEGINS TO WEAKEN ACROSS THE FORECAST AREA. MVFR CIGS AND LIGHT RAIN
EXPECTED OVER ATL AREA TAF SITES AFTER 12Z. LIGHT WEST WINDS WILL
SHIFT TO THE SOUTHWEST BY LATE THIS AFTERNOON. SOUTHWEST WINDS WILL
INCREASE TO 7-10KTS AFTER 12Z MONDAY AS THE SURFACE FRONT APPROACHES
ATL AFTER 16Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 69 47 61 38 60 / 5 10 70 10 5
ATLANTA 66 50 59 37 59 / 5 20 80 10 5
BLAIRSVILLE 63 44 52 32 58 / 5 50 80 5 5
CARTERSVILLE 66 46 57 33 58 / 5 40 80 5 5
COLUMBUS 67 50 66 39 63 / 5 10 30 10 10
GAINESVILLE 66 48 56 37 59 / 5 20 80 5 5
MACON 68 48 69 39 63 / 5 5 30 10 5
ROME 63 46 56 34 58 / 5 50 80 5 5
PEACHTREE CITY 67 47 62 34 61 / 5 10 70 10 5
VIDALIA 69 46 71 43 65 / 5 5 20 20 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
13
