000
FXUS62 KFFC 221039
AFDFFC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
539 AM EST SUN NOV 22 2009

.UPDATE...
EASTERLY FLOW HAS BROUGHT COOLER TEMPERATURES THAN ANTICIPATED.
TWEAKING FIRST PERIOD TEMPERATURES BASED UPON CURRENT TRENDS.

.PREV DISCUSSION... /ISSUED 515 AM EST SUN NOV 22 2009/

SHORT TERM /TODAY THROUGH TUESDAY/...
SHORT TERM MODELS HAVE INITIALIZED THE UPPER LEVEL LOW WELL... AND
ARE BETTER AGREEMENT WITH THE TRACK AS IT LIFTS NORTHEAST ACROSS
MS/AL/GA THROUGH THIS EVENING BEFORE BECOMING ABSORBED IN THE
LONGWAVE FLOW MONDAY MORNING.  MODELS ARE ALSO IN BETTER AGREEMENT
AS FAR AS HANDLING THE UPPER LOW DEEPENING OVER THE NORTHERN PLAINS
SUNDAY NIGHT AND EARLY MONDAY...ALTHOUGH SOME DISCREPANCIES CREEP IN
BY MONDAY NIGHT...MAINLY ECMWF IS DEEPER AND A BIT FURTHER EAST
WHICH IS IN LINE WITH THE CANADIAN.  SURFACE LOW TRACKS ALONG THE
GULF COAST TODAY BEFORE SHIFTING ACROSS FLORIDA/SOUTH GEORGIA
TONIGHT INTO THE ATLANTIC BY EARLY TOMORROW MORNING.  GFS/NAM
INDICATE A MESOHIGH DEVELOPS OVER THE CAROLINAS TODAY REINFORCING
THE DEVELOPING HYBRID DAMMING ACROSS THE AREA.

SHORT TERM MODELS HAVE BACKED OFF THE RAINFALL ASSOCIATED WITH THIS
INITIAL SYSTEM...AS EASTERLY FLOW AND HYBRID WEDGE SETS UP
TODAY...COOL STABLE FLOW WILL INHIBIT THUNDERSTORM DEVELOPMENT.
RAINFALL AMOUNTS ARE EXPECTED TO BE AROUND ONE INCH OR LESS AS
WELL SO NO FLOODING CONCERNS ARE ANTICIPATED. LIGHT RAIN WILL
CONTINUE THROUGH MONDAY. ALL MODELS HOLD ON TO EASTERLY FLOW AND
WEDGE CONDITIONS ON MONDAY AND TUESDAY...WITH GOOD LOW LEVEL
MOISTURE THROUGH THE END OF THE PERIOD. EXPECT LIGHT RAIN/DRIZZLE
E TO TAPER OFF TUESDAY WITH LINGERING LOW LEVEL CLOUDS THROUGH THE
DAY. HOW LONG THE CLOUDS LINGER WILL IMPACT AFTERNOON HIGHS WITH
LARGE DISCREPANCIES NOTED IN THE MAV/MET TEMPERATURES IN THE LATER
PERIODS DUE TO THE TIMING OF THE EROSION OF THE WEDGE...CSG HAS A
15 DEGREE DIFFERENCE BETWEEN THE TWO ON TUESDAY. WILL START WITH A
MAV/MET BLEND AT THIS TIME AS GFS TENDS TO ERODE THE DAMMING TOO
QUICK. TEMPERATURES ARE GOING TO BE PROBLEMATIC THROUGH THE
FORECAST PERIOD. GUIDANCE TEMPERATURES FOR TODAY ARE SEVERAL
DEGREES COOLER THAN CURRENT TEMPERATURES. MODELS SHOWING COOLER
EAST FLOW SETTING UP FASTER THAN IT CURRENTLY IS...THUS WILL GO
PRETTY CLOSE TO CURRENT TEMPERATURES FOR TODAY...ANTICIPATING THEM
TO REMAIN FAIRLY STEADY OR SLOWLY DROP THIS MORNING AND CONTINUE
FALLING THIS AFTERNOON AND OVERNIGHT.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A BROAD UPPER LEVEL TROUGH DOMINATES THE EXTENDED PORTIONS OF THE
FORECAST PERIOD...BOTH ECMWF AND GFS ARE FAIRLY CLOSE SPINNING IT
NEAR THE GREAT LAKES AREA WITH A SECONDARY LOBE DROPPING OUT OF
CANADA WEDNESDAY.  ECMWF AND CANADIAN MODELS ABSORB THE SECOND LOW
BY THURSDAY WHILE GFS ROTATES THE SECOND LOW ACROSS THE LOWER OHIO
VALLEY THURSDAY AND INTO NEW ENGLAND FRIDAY. BOTH MODELS PUSH A WEAK
SURFACE FRONT ACROSS THE SOUTHEAST WEDNESDAY...GFS IS DRIER THAN
ECMWF WHICH IS DRIER THAN IT WAS YESTERDAY.  BASED UPON THIS WILL
KEEP EXTENDED PERIODS DRY FOR NOW WITH COOLER THAN NORMAL
TEMPERATURES LATER IN THE WEEK.  SURFACE HIGH PRESSURE BEGINS
BUILDING INTO THE AREA FOR NEXT WEEKEND.

AVIATION...
COOL WEDGE STRENGTHENING OVER GA THIS MORNING AS SHOWN BY INCREASING
EASTERLY WINDS. RAIN WILL CONTINUE TO SPREAD NORTHWARD AS LOW
PRESSURE CURRENTLY NEAR MS COAST MOVES EAST TODAY. CEILINGS WILL
LOWER TO IFR BY NOON WITH VISIBILITY GENERALLY 3 TO 5SM IN RAIN.
CONVECTION SHOULD BE CONFINED TO AREAS SOUTH OF COLUMBUS TO MACON.
WINDS WILL REMAIN EAST TO NORTHEAST 10 TO 15KT WITH OCCASIONAL GUSTS
TO 20 TO 15KT.

.PRELIMINARY POINT TEMPS/POPS...
ATHENS          50  43  54  44  63 /  80  50  20   5   5
ATLANTA         52  44  55  45  61 /  80  50  20   5   5
BLAIRSVILLE     43  41  49  40  60 /  70  50  40   5   5
CARTERSVILLE    52  44  55  44  60 /  80  50  40   5   5
COLUMBUS        53  45  62  47  65 /  80  30   5   5   5
GAINESVILLE     49  42  52  43  60 /  80  50  40   5   5
MACON           53  45  62  44  65 /  80  30   5   5   5
ROME            54  46  56  44  61 /  70  50  40   5  10
PEACHTREE CITY  53  43  56  42  61 /  80  40  20   5   5
VIDALIA         53  45  66  45  66 /  80  60   5   5   5

.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.

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