FXUS63 KJKL 110242
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
942 PM EST THU DEC 10 2009

.SHORT TERM.../THE REST OF TONIGHT/...UPDATED

HIGH PRESSURE CURRENTLY CENTERED OVER THE MIDDLE MISSISSIPPI RIVER
VALLEY WILL CONTINUE TO WORK ITS WAY INTO EAST KENTUCKY OVERNIGHT... 
WITH CLEAR SKIES EXCEPT FOR A FEW HIGH LEVEL CLOUDS STREAMING
OVERHEAD TOWARD DAWN. SURFACE WINDS IN THE 5 TO 10 MILE PER HOUR
RANGE WILL CONTINUE TO KEEP THINGS MIXED A BIT AND ALLOW TEMPERATURES
FROM COMPLETELY CRASHING INTO THE SINGLE DIGITS. HOWEVER...THIS
GRADIENT IS GRADUALLY SLACKENING AND TEMPERATURES STILL LOOK TO FALL
TO THE 10 TO 15 DEGREE RANGE OVERNIGHT. WILL NOT UPDATE ANY SENSIBLE
WEATHER IN THE FORECAST...ONLY FRESHEN UP EVENING WORDING.

THE PREVIOUS SHORT TERM FORECAST DISCUSSION FOLLOWS...

/TONIGHT THROUGH SATURDAY/

AREA OF HIGH PRESSURE CURRENTLY CENTERED NEAR ARKLATEX WILL BUILD IN
ACROSS KENTUCKY TONIGHT. THIS WILL BRING CALMING WINDS AND ALLOW
TEMPERATURES TO BOTTOM OUT IN THE 10 TO 15 DEGREE RANGE FOR MOST
LOCATIONS. TEMPERATURES WILL REBOUND TO THE MID AND UPPER 30S
TOMORROW AND NEAR 40 CLOSE TO THE TENNESSEE BORDER.

HIGH PRESSURE WILL MAINTAIN CONTROL THROUGH FRIDAY NIGHT WITH WAA
KICKING IN AT 850 MB. THIS WILL ALLOW FOR VALLEYS TO BOTTOM OUT IN
THE MIDDLE TEENS...WHILE RIDGES STAY AROUND 20 DEGREES. 

LOW LEVEL JET WILL GRADUALLY RAMP UP THROUGH THE DAY ON SATURDAY
ALONG WITH THE APPROACH OF A SHORT WAVE TROUGH IN ZONAL FLOW. THE
SHORT WAVE WILL BRING A QUICK INCREASE IN HIGH CLOUDS...WHILE
ISENTROPIC LIFT ASSOCIATED WITH THE ENGAGING LOW LEVEL JET WILL
ATTEMPT TO BREAK THE VERY DRY LOW LEVEL AIR MASS THAT WILL BE IN
PLACE. SOME LIGHT RAIN WILL THREATEN THE TENNESSEE BORDER COUNTIES BY
LATE IN THE AFTERNOON AND WILL MAINTAIN A SLIGHT POP FOR THOSE
LOCATIONS. THERE IS A SMALL POSSIBILITY OF SOMETHING INITIALLY FROZEN
AT ONSET...HOWEVER THE WARM NOSE QUICKLY OVERTAKES...SO WILL CONTINUE
TO KEEP PRECIPITATION AS ALL LIQUID FOR NOW.

FOR TEMPERATURES...GENERALLY STUCK WITH PERSISTENCE...UNDERCUTTING
THE LOWS SOMEWHAT FOR TONIGHT WITH SINGLE DIGIT DEWPOINTS ADVECTING
IN. ALSO UNDERCUT HIGHS A BIT FOR SATURDAY WITH A COLD START AND
QUICK INCREASE IN CLOUD COVER BY EARLY AFTERNOON.

.LONG TERM.../SATURDAY NIGHT THROUGH THURSDAY/

LITTLE CHANGE TO THE PREVIOUS EXTENDED FORECAST AS MODELS REMAIN 
CONSISTENT WITH WEAKER SATURDAY NIGHT SYSTEM BEFORE DIVERGING WITH 
MORE COMPLEX SYSTEM IN THE EARLY MONDAY THROUGH LATE TUESDAY TIME 
FRAME. DID MAKE SOME POP INCREASES LATE SATURDAY NIGHT IN THE 
SOUTHEAST BUT LEFT WEATHER TYPE AS RAIN AS THE HIGHER ELEVATIONS OF 
THE SOUTHEASTERN ZONES SHOULD REMAIN WELL INTO AN ADVERTISED WARMER 
BOUNDARY LAYER. SYSTEM MONDAY INTO LATE TUESDAY HAS MORE POTENTIAL 
FOR EASTERN KENTUCKY AS ALL MODELS SHOW SOME ARCTIC AIR WORKING INTO 
THE REGION EARLY NEXT WEEK. MOST OF THE MODELS ARE TRENDING FURTHER 
SOUTH AND EAST WITH THE MAIN ENERGY AND PRECIPITATION ASSOCIATED 
WITH THE SYSTEM...LEAVING EASTERN KENTUCKY MOSTLY DRY. HOWEVER...THE 
GFS IS STILL SHOWING A MORE NORTH AND EAST TRACK WHICH COULD IMPACT 
THE CWA ON A MUCH LARGER SCALE. WITH SO MUCH DIFFERENCE BETWEEN 
MODELS HAVE OPTED FOR PERSISTENCE WITH THE FORECAST AND LEFT POPS IN 
THE MID CHANCE RANGE AT THIS TIME ACROSS THE ENTIRE REGION. AS THE 
SYSTEM EXITS WEDNESDAY...AREA FALLS UNDER COLDER HIGH PRESSURE 
THROUGH THE END OF THE WEEK. 

&&

.AVIATION.../00Z TO 24Z/

LINGERING GUSTY WEST WINDS WILL DIE DOWN SHORTLY AND THEN STAY AROUND
5 KTS FOR THE REST OF THE TAF PERIOD. COLD HIGH PRESSURE WILL THEN
KEEP THE CLOUDS AT BAY THROUGH FRIDAY...ALLOWING FOR VFR CONDITIONS
INTO THE WEEKEND.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...GEOGERIAN/SCHOETTMER
LONG TERM....MACZKO
AVIATION...GREIF