FXUS63 KPAH 040953
AFDPAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
350 AM CST FRI DEC 4 2009

.DISCUSSION...
MAIN CONCERN IS TEMPERATURES THROUGH THE WEEKEND. THE FOCUS TURNS TO 
POPS FOR SUNDAY NIGHT AND NEXT WEEK.

SOME MID/HIGH CLOUDS WILL STREAM NORTHEAST OVER WEST KENTUCKY TODAY 
INTO THIS EVENING...BUT SHOULD CLEAR THE AREA BY SATURDAY MORNING. 
THIS WILL COINCIDE WITH THE SURFACE HIGH SETTLING OVER THE 
REGION...WITH VERY DRY AIR IN PLACE. GOOD RADIATIONAL COOLING IS 
EXPECTED...WHICH WILL MAKE SATURDAY MORNING THE COOLEST OF THE 
SEASON...WITH LOWS 15-20 FROM WEST TO EAST ACROSS THE FORECAST AREA. 
SOME MID 20S WILL BE POSSIBLE NEAR KHOP...WHERE SOME CLOUDS MAY 
PROVIDE A BIT OF INSULATION. DESPITE PLENTIFUL SUNSHINE...SEE LITTLE 
REASON TO NOT FOLLOW THE COOLER MET NUMBERS CLOSELY THROUGH THE 
WEEKEND.

THE 00Z MODELS CONTINUE TO BRING AN UPPER-LEVEL IMPULSE EASTWARD 
THROUGH THE REGION IN STRONG WEST SOUTHWEST FLOW ALOFT. THE GFS IS 
SHARPER/STRONGER WITH THE TROUGH...WHICH RESULTS IN IT MOVING THE 
ASSOCIATED PRECIPITATION THROUGH THE REGION QUICKER...AND BUILDING 
SURFACE HIGH PRESSURE BEHIND THE BOUNDARY FOR MONDAY. THE ECMWF 
MAINTAINS WEST SOUTHWEST FLOW ALOFT THROUGHOUT...AND REALLY JUST 
WASHES OUT THE SURFACE TROUGH OVER THE REGION. 

THE GULF WILL BE TRYING TO OPEN UP SUNDAY...BUT RETURN FLOW AHEAD OF 
THIS SYSTEM WILL BE MEAGER AT BEST. FORCING LIKEWISE LOOKS WEAKER 
THAN PREVIOUSLY THOUGHT...ESPECIALLY IN THE ECMWF. THE MODELS HAVE 
HAD A SIGNAL FOR AT LEAST SOME LIGHT QPF THROUGOUT THE AREA SUNDAY 
NIGHT...BUT THE NAM AND ECMWF ARE NOW DELAYING IT. DECIDED TO 
INCREASE POPS TO 40S NORTH/50S SOUTH...BUT KNOCKED DOWN HPC QPF BY 
AT LEAST HALF...AS MOST AREAS WILL LIKELY BE UNDER A TENTH OF AN 
INCH FOR THIS EVENT. ALSO INTRODUCED A LINGERING 20-40 POP IN THE 
SOUTHEAST HALF OF THE AREA MONDAY MORNING. 

AS FOR PRECIPITATION TYPE...SNOW LOOKS LIKE A GOOD BET INITIALLY 
SUNDAY EVENING/OVERNIGHT IN THE WEST...BUT AS THE SYSTEM SHIFTS 
EAST...LOW-LEVEL WARMING OCCURS AND THE DEPTH OF SATURATION LOWERS. 
THIS RESULTS IN LITTLE CHANCE OF SNOW DEVELOPING. ANY PRECIPITATION 
IN THE EAST MONDAY MORNING WILL LIKELY BE IN THE FORM OF 
RAIN...HOPEFULLY THE TEMPERATURES WILL REMAIN AT OR ABOVE FREEZING. 
FOR NOW MENTIONED RAIN OR SNOW THROUGHOUT THE AREA SUNDAY 
NIGHT...AND JUST RAIN ON MONDAY...HOWEVER...WE WILL HAVE TO MONITOR 
TEMPERATURES CLOSELY FOR SOME ICING POTENTIAL EARLY MONDAY MORNING.

DID NOT MESS WITH MUCH BEYOND MONDAY...BUT THE 00Z ECMWF AND GFS
CONTINUE TO INDICATE A SIGNIFICANT WEATHER MAKER MOVING THROUGH THE 
REGION TUESDAY THROUGH WEDNESDAY. THEY BOTH HAVE A MID/UPPER LEVEL 
TROUGH BECOMING NEGATIVELY TILTED...AS IT PIVOTS THROUGH THE QUAD 
STATE TUESDAY NIGHT. WIND FIELDS WILL BE VERY IMPRESSIVE...AND WE 
ARE LIKELY TO BE IN THE WARM SECTOR...SUCH THAT IT WILL BE. IF ANY 
MOISTURE CAN RETURN AHEAD OF THIS SYSTEM...THUNDERSTORMS AND 
POSSIBLY SEVERE WEATHER COULD RESULT. RIGHT NOW IT IS DOUBTFUL THAT 
ENOUGH LOW-LEVEL MOISTURE WILL RETURN TO SUPPORT A SEVERE WEATHER 
EVENT...BUT WE WILL HAVE TO WATCH IT CLOSELY.

&&

.AVIATION...
SCATTERED MID CLOUDS WILL DEPART THE REGION BY SUNRISE. HIGH CIRRUS 
WILL CONTINUE TO STREAM OVERHEAD THROUGH THE GREATER PART OF THE 
DAY. WITH SOMEWHAT BETTER LOW-LEVEL MOISTURE OVER SOUTHEAST ILLINOIS 
AND SOUTHWEST INDIANA...SCATTERED CU DEVELOPMENT IS POSSIBLE BY LATE 
MORNING INTO THE AFTERNOON AT KOWB AND KEVV...BUT CONDITIONS SHOULD 
REMAIN VFR. LIGHT WEST NORTHWEST WINDS WILL PREVAIL. CLEARING SKIES 
AND LIGHT WINDS WILL BE THE RULE TONIGHT.

&&

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

$$

PUBLIC.....DRS
AVIATION...RP