FXUS64 KHUN 150850
AFDHUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
250 AM CST TUE DEC 15 2009
.SHORT TERM...THROUGH THURSDAY...
SFC COLD FRONT IS RAPIDLY PROGRESSING ACROSS THE HUN CWFA THIS
MORNING...AND AS OF 08Z IS ROUGHLY ALONG A COLUMBUS MS-ALBERTVILLE-
CROSSVILLE TN LINE. NO PCPN OF ANY REAL CONSEQUENCE MATERIALIZED
THIS FAR N...WITH THE BULK OF THE MOISTURE/GULF INFLOW HAVING BEEN
INTERCEPTED BY CONVECTION CLOSER TO THE GULF COAST. ONE OR TWO PTS
SE OF HSV HAVE ACTUALLY MEASURED MORE THAN A TRACE WITHIN -RA...BUT
LITTLE ELSE HAS BEEN OBSERVED. PREFRONTAL TEMPS/DEWPTS REMAIN IN THE
LOWER 60S. POSTFRONTAL TEMPS TAKE SOME TIME TO FALL OFF...BUT THEY
DO SO QUICKLY AS YOU APPROACH THE CENTER OF THE 1036MB HIGH...WHICH
IS CURRENTLY OVER NEBRASKA.
THERE IS NO QUESTION THAT WE HAVE HIT /OR ARE HITTING/ OUR HIGHS FOR
TODAY...AS LOW CLOUDS AND STRONG COLD AIR ADVECTION /CAA/ RESULT IN
SLOWLY FALLING TEMPS THROUGH THE DAY. OTHER QUESTION FOR TODAY IS
WHETHER ANYONE WILL SEE ANY ADDITIONAL -RA/-DZ AS THE UPPER TROUGH
AXIS PUSHES THROUGH LATE THIS AFTN. FEEL THAT THE MOISTURE IS FAR
TOO SHALLOW AND PVA TOO WEAK TO GET MUCH IF ANY ADDL PRECIP. IN
FACT...IF CURRENT SAT TRENDS ARE ANY INDICATION...WE MAY SEE A FEW
BREAKS IN THE CLOUDS EARLY THIS MORNING OR AGAIN LATE IN THE DAY.
SKIES SHOULD CLEAR FOR TONIGHT...THOUGH SOME LT CIRRUS MAY LINGER. A
STILL-TIGHT PRSR GRADIENT WILL KEEP WINDS IN THE 5-10KT RANGE SO
LOWS WILL BE MOSTLY ADVECTION-DRIVEN. BASED ON UPSTREAM OBS...FEEL
THE COOLER NAM MOS IS SLIGHTLY BETTER.
THE SUN MAY FINALLY MAKE A RETURN APPEARANCE TO THE REGION WEDNESDAY
/ASIDE FROM SOME THIN CIRRUS INDICATED BY MDL SOUNDINGS/. WEAK CAA
WILL LIKELY CONTINUE SO IT WILL NOT EXACTLY BE WARM...BUT HIGHS MAY
GET CLOSE TO SEASONAL AVGS. THE BOTTOM MAY FALL OUT WED NIGHT AS
GOOD RADNL COOLING AND A DRY ATMOSPHERE TAKE HOLD...AND HAVE
UNDERCUT THE GFS MOS. CONDITIONS SHOULD REBOUND NICELY FOR THURSDAY
AS THE SFC HIGH MOVES INTO THE MID-ATLANTIC.
.LONG TERM...FRIDAY THROUGH MONDAY...
SOME CUTOFF ENERGY OVER TX WILL EVENTUALLY SKIRT THE AREA TO THE
SOUTH LATE THURSDAY INTO FRIDAY. THE VAST MAJORITY OF OPRNL MODELS/
ENSEMBLES KEEP THE RAIN CONFINED TO THE FRONT WELL TO THE SOUTH.
THIS DRIER SOLN LOOKS MORE REASONABLE THAN THE MUCH-WETTER ECMWF...
THOUGH IT MAY INDUCE SOME RENEWED NORTHERLY FLOW AND COOLER WX.
WINTER WILL MAKE A REAPPEARANCE HEADING FOR THE WEEKEND AS A HIGHLY
AMPLIFIED PATTERN EVOLVES OVER THE GREAT LAKES/MIDWEST...AND A
POTENT SHORTWAVE SWINGS THROUGH THE AREA. AT THE VERY LEAST THIS
WILL DROP TEMPERATURES TO ROUGHLY 10 DEGREES BELOW NORMAL. OPRNL
GFS/ECMWF CONTINUE TO PRINT OUT SOME LT QPF IN THE VICINITY OF THIS
WAVE /THOUGH THE GFS IS BY FAR THE WETTEST OF THE GEFS MEMBERS/. THE
SYSTEM WILL BE RELATIVELY MOISTURE-STARVED...BUT LT PCPN IS
REASONABLE GIVEN THE TIME OF YEAR AND INTENSITY OF THE TROUGH. SFC
TEMPS AND SOUNDINGS SUGGEST AT LEAST SOME OF THAT FALLING AS SNOW AS
THE BLYR COOLS...BUT WILL LIKELY BE TOO LIGHT TO AMT TO VERY MUCH.
MODEL SPREAD PEAKS BY DAY 7 WITH THE ECMWF SENDING A TRAIN OF S/W
ENERGY THRU THE AREA IN NW FLOW...VERSUS THE MORE PROGRESSIVE/DRIER
GFS. HAVE TRENDED TOWARD THE GFS...BUT EITHER SOLN WILL MEAN A
CONTINUATION OF THE COOL PATTERN. THUS STAYED CLOSE TO OR JUST BELOW
THE GFSX MOS FOR TEMPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
HUNTSVILLE 50 30 49 26 56 / 10 0 0 0 0
SHOALS 48 30 50 26 56 / 10 0 0 0 0
VINEMONT 52 30 49 28 56 / 10 0 0 0 0
FAYETTEVILLE 46 28 46 27 55 / 10 0 0 0 0
ALBERTVILLE 53 31 50 27 56 / 20 0 0 0 0
FORT PAYNE 56 32 52 26 57 / 20 0 0 0 0
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
BCC
