FXUS63 KPAH 030441
AFDPAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
1041 PM CST WED DEC 2 2009

.UPDATE...
AMENDED THE AVIATION SECTION. NO CHANGES TO THE PUBLIC DISCUSSION
SECTION ISSUED AT 212 PM CST.

&&

.DISCUSSION...
CIRCULATION OF STRONG MID/UPPER LOW OVER ARKANSAS SHOWS UP CLEARLY 
IN RADAR AND SATELLITE IMAGERY THIS AFTERNOON. HIGH INTENSITY RADAR 
RETURNS NEAR THE UPPER LOW SEEM TO BE THE RESULT OF BRIGHT BANDING. 
SOME SLEET WAS REPORTED EARLIER TODAY OVER THE OZARKS. IN ANY 
CASE...THE ASSOCIATED SURFACE LOW WILL CONTINUE TO DEEPEN AS IT 
TRACKS NORTHEAST ACROSS THE KBWG /BOWLING GREEN/ AREA EARLY THIS 
EVENING. 

PRECIPITATION ASSOCIATED WITH THE DEFORMATION ZONE OF THE UPPER LOW 
SHOULD BE FOCUSED OVER THE LOWER OHIO VALLEY THROUGH EARLY EVENING. 
FORECAST MODEL SOUNDINGS INDICATE THE FREEZING LEVEL WILL GENERALLY 
REMAIN HIGH ENOUGH FOR ALL RAIN IN MOST AREAS. THE EXCEPTION IS 
ROUGHLY ALONG AND NORTHWEST OF A KMVN/KPOF LINE...WHERE SOME WET 
SNOW COULD MIX IN BEFORE ENDING TONIGHT AS FREEZING LEVEL DROPS 
BELOW 925 MB. MID LEVEL DRYING SHOULD PRETTY MUCH END ANY MEASURABLE 
PRECIP BY MIDNIGHT. EXTENSIVE LOW LEVEL MOISTURE WILL RESULT IN 
WIDESPREAD STRATOCU THROUGH DAYBREAK. COMBINATION OF CLOUDS AND WIND 
WILL KEEP THE ATMOSPHERE WELL MIXED...SO WILL NOT UNDERCUT MOS 
GUIDANCE TEMPS TONIGHT.

THOUGH THURSDAY THROUGH MONDAY WILL BE KEPT DRY...THE ACTIVE MID 
LEVEL FLOW PATTERN SUGGESTS PERIODS OF CLOUDINESS AND POSSIBLY 
FLURRIES OR SPRINKLES AT TIMES. A DEEP UPPER LOW OVER THE UPPER 
MISSISSIPPI VALLEY WILL LIFT NORTHEAST INTO FAR WESTERN ONTARIO BY 
THE WEEKEND. A TROUGH EXTENDING SOUTHWEST FROM THE UPPER LOW WILL 
SLOWLY APPROACH OUR FORECAST AREA THURSDAY THROUGH FRIDAY NIGHT. 
UNTIL THE PASSAGE OF THIS TROUGH...PERIODS OF CLOUDINESS AND SOME 
MID LEVEL RADAR ECHOES ARE LIKELY. THIS CLOUDINESS WILL AFFECT 
TEMPS. TRENDED FORECAST LOWS A BIT HIGHER THE NEXT FEW 
NIGHTS...WHILE DAYTIME HIGHS WERE TRENDED A BIT LOWER THAN MODEL 
GUIDANCE. HELD OFF ON THE MENTION OF ANY FLURRIES OR 
SPRINKLES.       

FOLLOWING THE MID LEVEL TROUGH PASSAGE...THE WEEKEND LOOKS DRY WITH 
A SLIGHT MODERATION IN TEMPS. A SURFACE HIGH WILL BUILD DIRECTLY 
OVER THE LOWER OHIO VALLEY SATURDAY...FOLLOWED BY LIGHT SOUTHERLY 
RETURN FLOW ON SUNDAY. DESPITE PLENTY OF SUN BOTH DAYS...TEMPS WILL 
REMAIN 5 TO 10 DEGREES BELOW NORMAL.

LOOKING INTO THE EARLY AND MIDDLE PART OF THE NEXT WORKWEEK...A MID 
LEVEL TROUGH OVER THE WESTERN STATES WILL MAKE SOME EASTWARD 
PROGRESS. THERE IS CONSIDERABLE MODEL VARIABILITY AS TO HOW FAST 
THIS TROUGH WILL MOVE. GENERALLY STAYED CLOSE TO THE 00Z GFS 
ENSEMBLE MEAN...WHICH WAS SLOWER THAN THE OPERATIONAL 00Z GFS/ECMWF 
RUNS. THIS IMPLIES PRECIP WILL HOLD OFF TIL MAINLY TUESDAY 
NIGHT/WEDNESDAY. PRECIP TYPE APPEARS MAINLY RAIN DUE TO WARMING 
ALOFT...THOUGH IT WILL BE CLOSE ENOUGH IN NORTHWESTERN/NORTHERN 
COUNTIES TO MENTION SNOW.   

&& 

.AVIATION...
LIGHT RETURNS SHOWING UP ACROSS SOUTHERN ILLINOIS SHOULD BE THE LAST
OF THE PRECIP...POSSIBLY AFFECTING KEVV AND KOWB UNTIL A BIT AFTER THE
06Z HOUR. OTHERWISE FOG SAT IMAGERY SHOWED DECREASING CLOUDS OVER
MISSOURI...THOUGH STRATO-CU CONTINUED TO ADVECT SOUTH ACROSS EVEN
WESTERN MISSOURI. WE WILL IMPROVE CIG CONDITIONS AND RAISE BASES
GRADUALLY THROUGH THE OVERNIGHT AS DRIER AIR CONTINUES TO WORK
UNDERNEATH FROM THE NORTHWEST. GUSTY WINDS SHOULD RELAX A TAD AS WELL
BUT CONTINUE UP NEAR 10 KTS AT TIMES FROM THE NORTHWEST. BY THURSDAY
AFTERNOON...COULD BE A FEW STRATO-CU STILL AROUND WITH SOME HIGH
CLOUDS AS WELL.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
MO...NONE.
IL...NONE.
IN...NONE.
&&

$$