FXUS64 KHUN 021747 AAC
AFDHUN

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1147 AM CST WED DEC 2 2009

.UPDATE...
18Z AVIATION UPDATE.

&&

.AVIATION...
IFR AND OCCASIONAL LIFR CIGS AND VISBYS ARE EXPECTED TO CONTINUE AT 
HSV AND MSL OVER THE NEXT FEW HOURS AS A LOW PRESSURE SYSTEM MOVES 
ACROSS THE AREA. SIGNIFICANT PRECIP HAS ENDED AT BOTH SITES...BUT 
OCCNL DZ WILL BE POSSIBLE THIS AFTERNOON. CIGS AND VISBYS WILL BEGIN 
TO IMPROVE INTO MVFR RANGE LATER THIS EVENING. WINDS WILL ALSO BE 
A PRIMARY CONCERN OVER THE NEXT 24 HRS...WITH A DIRECTION SHIFTING 
FROM ESE/SE NOW TO SW LATE IN THE AFTERNOON TO W OVERNIGHT. 

&&

.DISCUSSION... /ISSUED 1053 AM CST WED DEC 2 2009/
A CLOUDY...DRIZZLY...CHILLY DAY IS UNDERWAY ACROSS THE TENNESSEE
VALLEY REGION AS A LOW PRESSURE SYSTEM TRACKS ACROSS NW ALABAMA.
THE MORE WIDESPREAD AREA OF RAIN ASSOCIATED WITH THIS STORM HAS
MOVED NORTH AND EAST OF THE HUN CWA...THOUGH OCCASIONAL LIGHT RAIN
AND WIDESPREAD LOW CLOUDS AND DRIZZLE PERSIST IN ITS WAKE. LATEST
WV IMAGERY SHOWS A NOTABLE DRY PUNCH MOVING INTO THE AREA AHEAD OF
THE UPPER LEVEL STORM. THIS SHOULD KEEP SIGNIFICANT RAINFALL OUT
OF THE AREA THROUGH THE AFTERNOON HOURS. THUS POPS AND QPF HAVE
BEEN LOWERED AREA WIDE. THIS IS A SITUATION WHERE THERE COULD BE
SMALL AMOUNTS OF MEASURABLE PRECIP FROM PROLONGED PERIODS OF
DRIZZLE AND VERY LIGHT RAIN. SO THOUGH POPS ARE MUCH LOWER...IT
DOES NOT MEAN THINGS WILL DRY OUT.

CURRENT WIND ADVISORY WAS SCHEDULED TO EXPIRE AT 00Z. WE HAVE
RECEIVED A FEW REPORTS OF DOWNED TREES OVER NE ALABAMA THIS
MORNING. THERE ARE SOME INDICATIONS THAT THESE WIND GUSTS WERE
ENHANCED BY SOME FORM OF PRESSURE WAVE TRAILING THE BACK EDGE OF
THE PRECIP. HOWEVER NO ADDITIONAL REPORTS HAVE BEEN RECEIVED SINCE
AROUND 7-8AM. CURRENT OBS FROM THIS AREA INDICATE PEAK WIND GUSTS
IN THE 20-30 MPH RANGE...PRIMARILY IN THE HIGHER TERRAIN.
MEANWHILE...WINDS HAVE FALLEN OFF SIGNIFICANTLY CLOSER TO THE
SURFACE LOW. GIVEN CURRENT TRENDS...WE HAVE OPTED TO CANCEL THE
WIND ADVISORY FOR THE REST OF THE HUN CWA.

UPDATED GRIDDED AND TEXT PRODUCTS HAVE ALREADY BEEN SENT. AN
UPDATED NPW PRODUCT TO CANCEL THE WIND ADVISORY WILL BE ISSUED
SHORTLY.

&&

.PREV DISCUSSION... /ISSUED 325 AM CST WED DEC 2 2009/
LIGHT RAINFALL CONTINUES TO OVERSPREAD THE FORECAST AREA THIS
EARLY MORNING AS AN AREA OF LOW PRESSURE OUT OF THE NW GULF BEGINS
TO GRADUALLY TRACK TOWARD THE NE. THE GENERAL CONSENSUS OF THE
LATEST MODEL SUITES THIS MORNING BRING THE SFC LOW ACROSS NW AL
THIS AFTERNOON...WITH RAINFALL CONTINUING...IF NOT INCREASING IN
INTENSITY JUST A BIT. WIND SPEEDS ARE STILL XPCTED TO BE QUITE
GUSTY TODAY...ESPECIALLY E OF THE LOW...OR FOR AREAS ALONG AND E
OF I-65. AS SUCH...WILL MAINTAIN THE WIND ADVISORY FOR THESE AREAS
THROUGH 6 PM TONIGHT. ONLY OTHER REAL CHANGE TO THE FORECAST TODAY
WAS TO REMOVE ISOLATED TSTMS FROM THE GRIDS. AT THIS POINT...EVEN
WITH THE SFC LOW PASSING TO THE W...IT DOESN'T LOOK AS IF DEW PTS
AND LOW LEVEL INSTABILITY WILL RECOVER ENOUGH FOR CONVECTIVE
DEVELOPMENT. RAINFALL AND SFC WINDS ARE THEN XPCTED TO BEGIN
TAPERING OFF TONIGHT AS THE LOW MOVES OFF TOWARD THE NE STATES.

STRONG COLD AIR ADVECTION IS THEN SLATED TO BEGIN MOVING INTO THE TN 
VALLEY OVERNIGHT AND THU AS A STRONG/EXPANSIVE AREA OF HIGH PRESSURE 
BUILDS SEWD ACROSS THE NRN/CNTRL PLAINS. UNSEASONABLY COOL WX 
CONDITIONS ARE XPCTED TO PERSIST ACROSS THE REGION WELL THROUGH THE 
WEEKEND PERIOD AND INTO THE NEW WORK WEEK. ONE THING OF INTEREST 
THOUGH THE MODELS ARE HINTING AT IS ANOTHER STRONG AREA OF LOW 
PRESSURE DEVELOPING IN THE WRN GULF...WHICH SEEMS TO HAVE BEEN A 
CONSISTENT TREND NOW FOR THE PAST FEW DAYS. THE CONSENSUS OF THE 
GLOBAL MODELS WANT TO TAKE THIS NEXT LOW ON MORE OF AN EWD TRACK 
INTO SAT...BEFORE TAKING IT NEWD WELL INTO THE ATLANTIC SUN. THE 
MODELS ALSO HINT AT A GOOD AMOUNT OF MOISTURE OVERSPREADING THE 
AREA AGAIN ALONG THE BACK SIDE OF THE SFC LOW. WITH A POLAR AIR MASS 
ENTRENCHED ACROSS THE TN VALLEY...ANY PRECIP THAT MAY DEVELOP FROM 
LATE FRI NT THROUGH SAT MAY IN FACT TURN OUT TO BE SOME LIGHT SNOW. 
THICKNESS VALUES AND BUFR SOUNDINGS AT THIS POINT SEEM TO SUPPORT 
THIS THINKING...AND AS SUCH HAVE ADDED A SLIGHT CHANCE FOR SNOW OR 
RAIN/SNOW INTO THE FORECAST OVERNIGHT FRI AND SAT...AS THIS NEXT SFC 
LOW TRACKS ACROSS THE NRN GULF.

A BRIEF CLEARING TREND THEN LOOKS TO DEVELOP ACROSS THE AREA SUN AND 
MON ALTHOUGH AS STATED ABOVE...OVERALL TEMPS LOOK TO REMAIN BELOW 
NORMAL. YET ANOTHER AREA OF CYCLOGENESIS MAY THEN DEVELOP ACROSS THE 
WRN GULF ON TUE...AND BEGIN TO TRACK TOWARD THE NE WED IF THE LATEST 
MODEL SUITES ARE CLOSE. THICKNESS VALUES THOUGH DO NOT LOOK AS DENSE 
WITH THIS NEXT POSSIBLE SFC LOW...AND FOR NOW WILL MAINTAIN A SLIGHT 
CHANCE OR CHANCE FOR JUST SHOWERS AT THIS TIME TUE AND WED.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$

AVIATION/DISCUSSION...DL
PREV DISCUSSION...09