FXUS63 KJKL 060324
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
1024 PM EST SAT DEC 5 2009

.SHORT TERM.../TONIGHT/...UPDATED

TEMPS HAVE FALLEN OFF FASTER THAN WAS FORECAST FOR TONIGHT. MOST
LOCATIONS ARE AT OR NEAR THEIR DEW POINTS...WHICH WILL SLOW THE FALL.
HOWEVER...WITH SUCH A COLD AIR MASS IN PLACE...THERE IS NOT MUCH
LATENT HEAT TO BE RELEASED AFTER SATURATION. FROST FORMATION RATHER
THAN FOG FORMATION AND CONTINUED RADIATING SHOULD DEPRESS THE DEW
POINTS AND ALLOW TEMPS WELL DOWN INTO THE TEENS IN MOST PLACES.

THE PREVIOUS SHORT TERM FORECAST DISCUSSION FOLLOWS...

/TONIGHT THROUGH MONDAY NIGHT/

FEW FLURRIES IN OUR MOST ERN COUNTIES IS ALL THAT IS LEFT OF THE
RECENT SNOW STORM. STORM REPORTS HAVE INDICATED BETWEEN A TRACE AND 1
INCH FOR OUR WRN COUNTIES AND 1-3 INCHES EAST WITH A FEW LOCALIZED
REPORTS OF 4 INCHES... MAINLY IN THE HIGHER TERRAIN. CLOUD COVER HAS
BEEN TRYING TO BREAK UP BUT THE COLD CU HAS HUNG IN WITH THE UPSLOPE
FLOW PROVIDING JUST ENUF LIFT FROM THE DANIEL BOONE NATIONAL FOREST
AND EAST. EXPECT THE CU TO DIMINISH AND EVENTUALLY CLEAR AFTER SUNSET
WHEN THE LLVL INVERSION SETS UP AND THE OROGRAPHIC LIFT ENDS. THE
CLEARING OVERNIGHT WILL ALLOW TEMPS TO DROP INTO THE UPPER TEENS FOR
MOST OF THE CWFA. AREAS IN OUR NRN COUNTIES AND THE WRN SLOPES OF THE
DANIEL BOONE RIDGE MAY KEEP JUST ENUF BREEZE THAT THEY WILL REMAIN A
TAD WARMER AND WILL FORECAST GENERALLY AROUND 20 FOR THEM. 

FULL SUN AND LIGHT WINDS ON SUNDAY WITH THE HIGH BUILDING IN WILL
ALLOW TEMPS TO REBOUND TO THE LOWER 40S. WILL HAVE TO KEEP AN EYE ON
SNOW COVER AS THE SUN WILL HAVE TO MELT THE SNOW BEFORE IT CAN WARM
THE GROUND AND THIS MAY SLOW THE WARM UP TO KEEP TEMPS A FEW DEG
COOLER. HIGH PRESSURE WILL BE DIRECTLY OVERHEAD SUN NIGHT... SO
EXPECTING A RIDGE/VALLEY SPLIT TO LOW TEMPS WITH MID 20S VALLEYS AND
LOWER 30S RIDGES. HIGH PRESSURE TO SLIDE TO THE MID ATLANTIC SEABOARD
FOR MONDAY AND WINDS WILL SHIFT TO THE SE WITH A DOWNSLOPE/WARMING
COMPONENT... AND WITH NO SNOW... TEMPS WILL MAKE IT INTO THE MID 40S
IN SPITE OF AN INFLUX OF MID AND HIGHER CLOUDS. MONDAY NIGHT WILL SEE
THE NEXT LOW PRESSURE SLIDE INTO THE NRN MO CORN BELT BRINGING AN
INCREASE IN CLOUD COVER. SREF BRINGS THE PCPN INTO ERN KY DURING THIS
TIME PERIOD BUT IS MUCH STRONGER THAN THE GFS/ECMWF. WILL BRING A
SLIGHT CHC POP INTO THE FCST MONDAY AND WAIT FOR MORE CONFIRMATION OF
SIGNIFICANT PCPN. IN ANY CASE...ANY PCPN FOR MONDAY WILL BE LIQUID.

.LONG TERM.../TUESDAY THROUGH SATURDAY/

ONCE AGAIN TODAY FORECAST MODELS ARE FAIRLY STABLE IN THEIR
DEPICTIONS OF THE SYNOPTIC PATTERN THROUGH THE PERIOD. THE BIG
TICKET ITEM WILL BE A SHORTWAVE WHICH WILL SWEEP ACROSS THE OHIO
VALLEY ON WEDNESDAY. ATTENDANT COLD FRONT WILL SWEEP THROUGH THE
AREA LATE TUESDAY NIGHT AND WE CONTINUED TO RAMP UP POPS FOR THAT
PERIOD. THE BIGGEST CONCERN CONTINUES TO BE THE POTENTIAL WINDS WITH
THE SYSTEM THOUGH. NEGATIVE TILT TO THE SHORTWAVE AND PROGGED LOW
LEVEL JET SPEEDS APPROACHING 75 KTS AT 850 MB ON THE GFS POINT TO A
POTENTIAL ADVISORY CRITERIA WIND EVENT... IF NOT GREATER... SO WILL
CONTINUE TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK. THE GUSTY
WINDS WILL CONTINUE WEDNESDAY INTO WEDNESDAY NIGHT IN THE COLD
ADVECTION BEHIND THE FRONT. IT IS WITH THE POST FRONTAL AIR MASS
WEDNESDAY NIGHT INTO THURSDAY THAT BIG DIFFERENCES CONTINUE TO EXIST
BETWEEN THE GFS AND ECMWF. WE CONTINUED TO FAVOR THE WARMER ECMWF AS
PROGRESSIVE FLOW SHOULD MEAN LESS OVERALL INFUSION OF COLD AIR THIS
FAR SOUTH.

THE FLOW WILL BECOME MORE ZONAL FROM THURSDAY NIGHT THROUGH SATURDAY
WITH A PRONOUNCED SPLIT FLOW PATTERN OVER THE CONUS. HIGH PRESSURE
WILL MOVE ACROSS THE AREA THURSDAY AND THURSDAY NIGHT WITH DRY
CONDITIONS EXPECTED. FAST MOVING WEAK DISTURBANCES ARE THEN EXPECTED
TO ZIP ACROSS THE AREA IN THE FAST FLOW ALOFT FRIDAY AND SATURDAY
BRINGING A SMALL THREAT FOR A SHOWER EACH PERIOD. WILL ONLY
ADVERTISE RAIN FOR THESE PERIODS NOW AS TEMPERATURES SHOULD MODERATE
A BIT... ALBEIT STAYING BELOW NORMAL EACH DAY. WE KEPT TEMPS FOR THE
END OF THE PERIOD IN CLOSE AGREEMENT WITH THE 05/12Z GFSX MOS
GUIDANCE NUMBERS.

&&

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

MVFR STRATOCU WILL LINGER IN FAR SOUTHEASTERN KENTUCKY A FEW MORE
HOURS BEFORE DISSIPATING. AN AREA OF HIGH PRESSURE WILL PROVIDE VFR
CONDITIONS FOR THE REST OF THE PERIOD...WITH ONLY AN INCREASE IN HIGH
CLOUDS EXPECTED AFTER 18Z OUT AHEAD OF THE NEXT APPROACHING SYSTEM.

&&

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

&&

$$

SHORT TERM...DUSTY/HAL
LONG TERM....ABE
AVIATION...GEOGERIAN