FXUS63 KLMK 301941
AFDLMK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
241 PM EST MON NOV 30 2009

.SHORT TERM (TONIGHT AND TUESDAY)...

SURFACE HIGH PRESSURE OVER OKLAHOMA WILL CONTINUE TO MOVE EASTWARD 
AND BUILD OVER THE OHIO VALLEY TONIGHT INTO TUESDAY. SKIES WILL 
BEGIN CLEARING FROM WEST TO EAST THIS EVENING AND TEMPERATURES WILL 
FALL INTO THE LOW 30S. SOME PATCHY FOG WILL BE POSSIBLE IN THE 
NORMAL FOG PRONE AREAS ACROSS SOUTH CENTRAL KENTUCKY WHERE MORE 
PRECIPITATION FELL OVERNIGHT. 

ON TUESDAY...A RIDGE WILL BUILD OVER THE REGION AND SKIES SHOULD 
REMAIN MOSTLY CLEAR WITH DAYTIME HIGHS WARMING BACK INTO THE LOW TO 
MID 50S. SOUTHWEST WINDS WILL BE SOUTHEASTERLY AHEAD OF A POTENT LOW 
PRESSURE SYSTEM THAT WILL MOVE INTO THE AREA ON WEDNESDAY.

.LONG TERM (TUESDAY NIGHT - MONDAY)...

WEDNESDAY AND THURSDAY...

A COLD ARCTIC BLAST WILL BE THE BIG STORY FOR THIS FORECAST.

IN THE UPPER ATMOSPHERE A DEEP CLOSED SOUTHERN STREAM LOW WILL TRACK 
ACROSS TEXAS AND THEN BECOME ABSORBED INTO A NORTHERN STREAM TROUGH 
AS THEY MOVE ACROSS THE MISSISSIPPI VALLEY. THE RESULT WILL BE A 
DEEPENING SURFACE LOW THAT WILL TRACK NORTHEAST FROM LOUISIANA TO 
MICHIGAN. THE SHORT RANGE MODELS ARE IN SOME DISAGREEMENT ON THE 
TIMING AND TRACK OF THE SYSTEM WITH THE NAM A LITTLE FURTHER WEST 
THAN THE GFS. REGARDLESS... THIS SYSTEM WILL BRING RAIN INTO THE 
LOWER OHIO VALLEY DURING THE DAY WEDNESDAY AS WELL AS GUSTY WINDS. 

A STRONG COLD FRONT WILL SWEEP ACROSS THE FORECAST AREA WEDNESDAY 
NIGHT WITH WITH RAIN CHANGING TO SNOW. MOST OF THE MOISTURE WILL BE 
OUT OF THE AREA BY THE TIME THE CHANGE OVER OCCURS AND THE GROUND 
WILL BE FAIRLY WARM SO NO SNOW ACCUMULATION IS EXPECTED WEDNESDAY 
NIGHT. 

COLD AIR WILL CONTINUE TO ADVECT INTO THE REGION DURING THE DAY 
THURSDAY. SKIES WILL REMAIN CLOUDY AND LIGHT SNOW SHOWERS WILL BE 
NOTED AS THE COLD AIR SQUEEZES THE RESIDUAL MOISTURE OUT OF THE 
AIRMASS. 

TEMPERATURES WEDNESDAY WILL WARM INTO INTO THE UPPER 40S EVEN WITH 
THE CLOUD COVER AND RAIN. LOWS WEDNESDAY NIGHT WILL FALL INTO THE 
LOWER 30S AND WILL HAVE A HARD TIME REACHING THE UPPER 30S DURING 
THE AFTERNOON. 
  

FRIDAY THROUGH MONDAY...

A DEEP TROUGH WILL REMAIN IN PLACE ACROSS THE GREAT LAKES AND OHIO 
VALLEY FOR MUCH OF THE WEEKEND. DRY WEATHER IS EXPECTED BUT 
TEMPERATURES FRIDAY AND SATURDAY WILL BE SOME 10 TO 15 DEGREES BELOW 
NORMAL FOR EARLY DECEMBER. SOME WARMER AIR WILL BEGIN TO ADVECT INTO 
THE REGION LATE SUNDAY AND MONDAY.

&&

.AVIATION (18Z TAF ISSUANCE)...

MVFR CONDITIONS WILL CONTINUE THE NEXT SEVERAL HOURS AT MOST TAF 
SITES...SDF AND LEX WILL BECOME VFR BY AROUND 22Z WITH CIGS AROUND 4 
TO 6 KFT PERSIST THROUGH EARLY EVENING BEFORE CLEARING BEGINS AT 
SDF. LEX WILL STAY IN CLOUD COVER THROUGH MOST OF THE NIGHT. BWG 
WILL CONTINUE TO HAVE LOW CIGS AROUND 1-2 KFT THROUGH THE REST OF 
THE AFTERNOON BEFORE BEGINNING TO CLEAR OUT AROUND 03Z. DECIDED TO 
KEEP THE CLOUD COVER AROUND LONGER AS SOUNDING AND MODEL DATA 
INDICATE LOW LEVEL MOISTURE MOVING OUT MORE SLOWLY THAN EARLIER 
EXPECTED.

BY MORNING...SOME PATCHY FOG MAY DEVELOP NEAR BWG AND BROUGHT VSBYS 
DOWN TO 4SM WITH CLEAR SKIES. WINDS WILL REMAIN FROM THE NORTHWEST 
THROUGH EVENING BEFORE SHIFTING TO THE WEST/SOUTHWEST OVERNIGHT UP 
TO 5 KTS.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&

$$

SHORT TERM........LS
LONG TERM.........JA
AVIATION..........LS