FXUS63 KLMK 061522
AFDLMK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1022 AM EST SUN DEC 6 2009

...FORECAST UPDATE...

ONLY A MINOR UPDATE THIS MORNING TO ADJUST TEMPS UP IN THE WESTERN 
FORECAST AREA (FA) AND TWEAK SKY GRIDS.  WITH HIGH PRESSURE CENTERED 
TO OUR EAST OVER SOUTHERN OHIO AND WEST VIRGINIA...TODAY WILL BE A 
QUIET WEATHER DAY.  UPPER LEVEL CLOUDS WILL GRADUALLY INCREASE FROM 
SW TO NE TODAY AND HAVE TWEAK SKY GRIDS TO SHOW THIS TREND FOR THIS 
AFTERNOON.  HOWEVER...CLOUD DECK SHOULD STAY TRANSPARENT ENOUGH TO 
ALLOW PLENTY OF SUNSHINE THROUGH.  SINCE MORNING TEMPS HAVE RISEN A 
BIT MORE IN THE WESTERN FA THAN PREVIOUSLY FORECAST...HAVE UPPED 
HIGHS A DEGREE OR TWO IN THIS AREA. GENERALLY WE SHOULD SEE HIGHS IN 
THE LOW TO MID 40S THIS AFTERNOON.

.SHORT TERM (TODAY THROUGH MONDAY)...

UPPER AIR FLOW CURRENTLY SHOWS A BLOCKING RIDGE OVER SOUTHERN ALASKA 
WITH DEEP COLD TROUGHS BRACKETING THIS RIDGE LOCATED ACROSS THE 
PACIFIC NORTHWEST AND SOUTH OF THE WESTERN ALEUTIANS. AS ARCTIC AIR 
POURS INTO THE PACIFIC NORTHWEST...THIS TROUGH WILL SAG SOUTHWARD 
TOWARDS NORTHERN CALIFORNIA BY MONDAY AFTERNOON. A SHORTWAVE TROUGH 
NOW OVER THE CENTRAL ROCKIES WILL DE-AMPLIFY AND WEAKEN AS IT 
CROSSES MISSOURI LATE SUNDAY. 

THE SURFACE REFLECTION OF THIS SYSTEM WILL BE WEAK...BUT WILL SHOW 
UP AS AN INVERTED SURFACE TROUGH OVER MISSOURI EARLY MONDAY.

EXPECT A MOSTLY SUNNY DAY WITH SOME INCREASING HIGH CLOUDINESS THIS 
AFTERNOON AS A SEASONABLY COLD AIR MASS REMAINS OVER THE LOWER OHIO 
VALLEY. HIGH PRESSURE RIGHT OVERHEAD ATTM WILL MOVE EAST TOWARDS THE 
MID ATLANTIC COAST BY THIS EVENING. SURFACE WINDS WILL BECOME LIGHT 
SOUTHERLY THIS AFTERNOON. AFTER A COLD START...TEMPS SHOULD MODERATE 
A BIT INTO THE LOWER 40S THIS AFTERNOON.  

EXPECT INCREASING CLOUDINESS THIS EVENING AS WARM AIR ADVECTION 
STRENGTHENS AHEAD OF THE PREVIOUSLY MENTIONED INVERTED TROUGH OVER 
MISSOURI. MOISTURE ASSOCIATED WITH THIS SYSTEM WILL BE SCANT. 
HOWEVER...SOME SPRINKLES OR VERY LIGHT SNOW SHOWERS ARE POSSIBLE 
TOWARDS DAWN ON MONDAY WEST OF INTERSTATE 65...AND LATER IN THE 
MORNING ACROSS THE BLUEGRASS AND THE LAKE CUMBERLAND AREAS. FORECAST 
SOUNDINGS SHOW MUCH OF THE ATMOSPHERE BELOW FREEZING...ALTHOUGH 
SURFACE TEMPS MAY WARM TO A COUPLE OF DEGREES ABOVE FREEZING MONDAY 
MORNING. VERY LIMITED MOISTURE WILL BE AVAILABLE IN THE PREFERRED 
SNOW FORMATION REGIONS BETWEEN -10C AND -20C...AND SO DO NOT EXPECT 
MUCH IN THE WAY OF ACCUMULATIONS. CLOUDS WILL LIKELY LIMIT HIGHS 
MONDAY TO AROUND 40 OR SO. WINDS WILL STAY LIGHT MONDAY FROM THE 
SOUTHWEST.

.LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...

TUESDAY AND WEDNESDAY...

A STRONG UPPER LEVEL JET ROTATING THROUGH THE BASE OF A WEST COAST 
TROUGH AT THE BEGINNING OF THIS FORECAST PERIOD WILL QUICKLY 
TRANSVERSE THE UNITED STATES... ARRIVING IN THE LOWER OHIO VALLEY BY 
WEDNESDAY AFTERNOON. THIS WILL SERVE TO PUSH THE UPPER LEVEL TROUGH 
QUICKLY INTO THE REGION. IN THE LOWER ATMOSPHERE A DEEPENING LOW 
WILL TRACK FROM OKLAHOMA TUESDAY NIGHT INTO MICHIGAN BY WEDNESDAY 
AFTERNOON. WITH A TIGHTENING SOUTHERLY GRADIENT AHEAD OF THE LOW 
WARM MOIST AIR WILL STREAM INTO THE LOWER OHIO VALLEY WITH SHOWERS 
OVERSPREADING THE FORECAST AREA TUESDAY AFTERNOON AND CONTINUING 
TUESDAY NIGHT. STRONG LOW LEVEL WINDS SHOULD REMAIN ELEVATED MOST OF 
TUESDAY NIGHT BUT SOME STRONG GUSTS MAY MAKE IT TO THE SURFACE 
AROUND 12Z WEDNESDAY. A STRONG COLD FRONT WILL SWEEP THROUGH THE 
REGION WEDNESDAY MORNING WITH GUSTY WESTERLY WINDS NOTED WEDNESDAY 
AFTERNOON. LINGERING SHOWERS WILL GRADUALLY CHANGE TO LIGHT SNOW 
SHOWERS BY AFTERNOON AS WELL.

TEMPERATURES WILL BE ON SOMEWHAT OF A ROLLER COASTER RIDE WITH THE 
WARMEST READINGS NOTED JUST BEFORE THE FRONTAL PASSAGE WEDNESDAY 
MORNING. 

THURSDAY - SATURDAY... 

YET ANOTHER SOUTHERN STREAM SYSTEM WILL AFFECT THE AREA ON FRIDAY 
NIGHT/SAT.  AT THIS POINT...IT DOES LOOK LIKE SOME FROZEN PRECIP 
WOULD BE POSSIBLE.  TEMPS LOOK TO REMAIN BELOW NORMAL IN THE LAST 
PART OF THE LONG TERM.

&&

.AVIATION (12Z TAF ISSUANCE)...

VFR CONDITIONS EXPECTED THROUGH AROUND 06Z MONDAY. HIGH PRESSURE 
WILL SLIDE EAST OF KENTUCKY TODAY. SOUTHEAST WINDS WILL INCREASE TO 
AROUND 5KT THIS AFTERNOON AND REMAIN FROM THE SOUTH AROUND 5KT 
TONIGHT. 

HIGH CLOUDS ABOVE 12K FEET WILL INCREASE THIS AFTERNOON. CLOUDS WILL 
LOWER A BIT TOWARDS 12Z MONDAY AS A WEAK DISTURBANCE APPROACHES FROM 
THE WEST. HOWEVER...CIGS WILL REMAIN VFR AT LEAST THROUGH 09Z. 
MONDAY.

&&

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

$$

UPDATE.........AML
SHORT TERM.....JSD
LONG TERM......JA
AVIATION.......JSD