FXUS63 KJKL 041655
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
1155 AM EST THU NOV 4 2004

.DISCUSSION...

PESKY SHOWERS FINALLY EXITING EASTERN ZONES...AS SFC FRONTAL 
BOUNDARY MARCHES ACROSS FA. COOLER AIR AND GUSTIER SFC WINDS BEHIND 
FRONT ARE EVIDENT IN SFC OBS. TEMPERATURES IN MID TO UPPER 50S 
ALREADY SETTLING IN ACROSS CENTRL KY. THIS WILL PUT A NEGATIVE TILT 
ON THE THERMOMETER THIS AFTERNOON...RESULTING IN A FALL RATHER THEN 
CLIMB IN TEMPERATURES THROUGH THE AFTERNOON.

UPDATE ALREADY OUT TO REMPVE MORNING WORDING. PACKAGE OVERALL WAS ON 
TARGET...KEEPING HIGHS NEAR 60 AND GUSTY SW SFC WINDS OVER MOST OF 
FA FOR PM. KEPT IN SLT CHANCE POPS MOST ZONES FOR REMAINDER OF DAY 
WITH POSSIBLE POP UP SHOWER A POSSIBILITY. A BIT MORE INSTABILITY 
AND LIFT ON OUR VA BORDER COUNTIES...SO LEFT LOW CHANCE POPS IN FAR 
EAST ZONES.

&&

.PREV DISCUSSION...

530 AM EST THU NOV 4 2004

SFC LOW PRESSURE LOCATED OVER CENTRAL INDIANA ACCELERATING 
NORTHWARD...WITH COLD FRONT NEARING CENTRAL KENTUCKY...AND 
CONTINUING TO MAKE GOOD PROGRESS TO THE EAST. GOOD SOAKING RAIN 
OVERNIGHT...WITH UP TO 2 INCHES IN SPOTS ALONG THE I-75 CORRIDOR AND 
WHERE IT INTERSECTS I-64. STILL SOME GOOD CONVECTION GOING ON WITH 
THE OCCASIONAL LIGHTNING STRIKE. MENTIONED THUNDER EARLY...WITH BEST 
POPS IN THE EASTERN HALF OF THE CWA. HIGH TEMPS WILL BE TRICKY 
TODAY...AS WAA OUT AHEAD OF THE FRONT HAS LED TO RISING TEMPS 
OVERNIGHT FOR MOST SPOTS. AM COUNTING ON A 12Z HIGH AS COOLER AIR 
RUSHES IN RAPIDLY IN THE FRONT'S WAKE...STEADYING TEMPS FOR THE REST 
OF THE DAY.  

STRONG SUBSIDENCE WILL TRAP MOISTURE IN THE LOW LEVELS...AS PREVIOUS 
FORECAST HAD PEGGED...WITH A FEW STRAY SHOWERS LINGERING THROUGH THE 
EVENING HOURS. FORECAST SOUNDINGS THAN TRANSITION TO MORE OF A 
DRIZZLE POTENTIAL LATER...SO MENTIONED DRIZZLE WHERE BEST UPSLOPE 
WIND FETCH WILL BE. 

FROST WITH POTENTIALLY SOME ISOLATED FREEZES STILL LOOKS GOOD FOR 
FRIDAY NIGHT...HOWEVER ONLY SNAG WILL BE WAA ADVECTION TO TAKE PLACE 
DURING THE OVERNIGHT. WSW WINDS WILL KEEP THE RIDGES FROM DROPPING 
OFF TOO RAPIDLY. WILL CONTINUE TO LET THE HWO DO MORE OF TALKING ON 
THE FROST/FREEZE POTENTIAL WITH CALM WINDS STILL IN QUESTION. 

HEIGHT RECOVERIES AND 850 TEMPS CONTINUE THROUGH SATURDAY SO HAVE 
NUDGED HIGHS UP A BIT. MORE SOUTHWESTERLY FLOW OUT OF NEXT WEAK 
DISTURBANCE TO BRUSH BY FROM THE NORTH...LEADING TO ANOTHER SPLIT ON 
SATURDAY NIGHT AS VALLEYS DECOUPLE. LEFT SUNDAY THROUGH WEDNESDAY 
INTACT.
  
&&

550 PM EST WED NOV 3 2004

QUICK UPDATE. WINDS HAVE DECREASED ACROSS THE AREA AND OVERNIGHT 
FCST PICKED UP ON THIS BUT MUCH LATER. LATEST GFS MODEL STILL KEEPS 
100 POP FOR THE AREA ALTHOUGH THE QPF DOES NOT LOOK IMPRESSIVE. PW 
IS HIGH ENOUGH TO PRODUCE ISOLATED HEAVY RAIN AND WILL KEEP 
MENTION...BUT NOT EXPECTING GENERALIZED HEAVY RAIN FOR HYDRO 
CONCERNS. STILL FEEL THAT ALMOST EVERYONE SHOULD MEASURE.

445 PM EST WED NOV 3 2004

20Z SFC ANALYSIS HAD AN AREA OF LOW PRESSURE CENTERED OVER NW MS 
WITH A WARM FRONT EXTENDING EAST ACROSS THE NORTHERN PORTIONS OF THE 
GULF COAST STATES AND INTO THE MID ATLANTIC STATES. ONE BATCH OF 
RAIN WAS OVER NE TN AND SOUTHEASTERN KY. ADDITIONAL SHOWERS ARE NOW 
DEVELOPING AHEAD OF THIS LOW AND WARM FRONT OVER NORTHERN ALABAMA 
AND MS AND WESTERN TN. THE SFC LOW IS IN RESPONSE TO AN UPPER LOW 
NOW OVER CENTRAL OK.

THE MODELS TAKE THE LOW INTO THE EASTERN GREAT LAKES BY 0Z FRI. AT 
THE SAME TIME THE SFC LOW IS FORECAST TO DEEPEN AND TRACK UP THE MS 
VALLEY AND INTO THE OH VALLEY TONIGHT. LIFT AHEAD OF THIS SYSTEM 
SHOULD GENERATE A DECENT SHOT OF RAIN TONIGHT. PWS ARE FORECAST TO 
RISE INTO THE 1.5" RANGE OVERNIGHT TONIGHT. WENT WITH RAIN COULD BE 
HEAVY AT TIMES IN THE GRIDS. SOME FACTORS LIMITING PRECIP AMOUNTS 
WILL BE THE DOWNSLOPE FLOW INTO THE VA BORDER COUNTIES. 12Z GFS AND 
ETA RUNS BOTH SEEM TO INDICATE THIS AS WELL. ALSO...THE REGION WILL 
NOT BE UNDER THE FAVORABLE REGION OF THE UPPER JET EITHER. AFTER THE 
INITIAL SHOT EXITS THE REGION...MUCH OF THE PRECIP WILL LIKELY HOLD 
OFF UNTIL AFTER MIDNIGHT WHEN LIFT AND MOISTURE WILL BE THE BEST. 
LOW TEMPS ARE A LITTLE PROBLEMATIC. WARM ADVECTION WILL BE BALANCED 
BY SOME WETBULBING. TEMPS AT 0Z OR SHORTLY AFTER MAY IN FACT BE THE 
LOW OR THE LOWS MAY OCCUR AROUND OR SHORTLY AFTER 12Z WITH THE 
FROPA. MODELS ALSO INDICATE A BIT OF A DRY SLOT AFTER THE COLD FRONT 
TRAILING S FROM THE LOW CROSSES THE REGION ON FRI MORNING OR EARLY 
AFTERNOON. THE ETA APPEARS TO BE A TAD SLOWER WITH THE FRONT THAN 
THE ETA. PUT IN A BRIEF PERIOD OF LOWER SKY COVER AROUND MIDDAY IN 
THE GRIDS TO ACCOUNT FOR THE DRY SLOT. THIS ALSO COULD ALLOW TEMPS 
TO RISE ABOVE MAV GUIDANCE. FOR NOW DID NOT GO THAT AGGRESSIVE WITH 
HIGHS AND STAYED CLOSE TO THE PREVIOUS FORECAST WHICH WAS JUST A 
DEGREE OR TWO ABOVE THE 12Z MAV NUMBERS.

HIGH PRESSURE BEGINS TO BUILD INTO THE REGION THU NIGHT...BUT LOW 
LEVEL MOISTURE WILL REMAIN TRAPPED BELOW SUBSIDENCE INVERSION FOR A 
TIME AND KEEP CLOUDS MOSTLY CLOUDY AS THE WRAPAROUND MOISTURE WORKS 
IN ON NW UPSLOPE FLOW. WENT WITH A CHANCE OF SOME UPSLOPE RAIN 
SHOWERS ON THU EVENING...LINGERING THEM A LITTLE LONGER ON THE VA 
BORDER. FRI SHOULD HAVE HIGH TEMPS OF 5 TO 10 DEGREES BELOW NORMAL 
AS HIGH PRESSURE CONTINUES TO WORK IN. WITH HIGH PRESSURE BUILDING 
EAST INTO THE TN VALLEY THERE SHOULD BE DECENT RADIATIONAL COOLING 
ON FRI NIGHT. SOME VALLEY LOCATIONS WILL LIKELY DECOUPLE ENOUGH FOR 
A MINOR TO MODERATE RIDGE VALLEY TEMP SPLIT. MENTIONED SOME PATCHY 
FROST IN THE VALLEYS. SOME OF THE VALLEYS MAY HAVE AN OPPORTUNITY 
FOR A HARD FREEZE IF PRESS GRADIENT DECEASES ENOUGH TO SLACKEN 
WINDS. MET AND MAV GUIDANCE TEMPS ARE BOTH BELOW FREEZING AT LOZ FOR 
FRI NIGHT...BUT REMAIN IN THE MID 30S AT JKL. TEMPS SHOULD MODERATE 
ON SAT AS 8H THERMAL TROUGH WILL HAVE PASSED TO THE EAST. MEX 
NUMBERS WERE CLOSE TO ENSEMBLE MEANS FOR SAT HIGH TEMPS SO FOLLOWED 
MEX NUMBERS CLOSELY.

EXTENDED (SUNDAY-TUESDAY)

STILL QUITE A BIT OF RUN-TO-RUN VARIABILITY WITH UPPER LEVEL PATTERN 
IN THE EXTENDED. KEPT THINGS DRY...WHICH IS NICELY SUPPORTED 
BY MOS AND MOS ENS MEAN...WHICH BOTH PRODUCE PUNY POPS THROUGH THE 
PERIODS. AS FAR AS TEMPS GO...BECAUSE OF THE CONTINUING UNCERTAINTY 
IN THE STRENGTH...TIMING...AND POSITION OF WHAT LOOKS TO BE A NICE 
JET-DUG EASTERN CONUS TROUGH...AND EVEN MORE IMPORTANTLY...THE 
FOLLOWING S/WV RIDGING THAT COULD POTENTIALLY HELP TO AMPLIFY COLD 
AIR INTRUSION INTO THE CWA...LEANED QUITE A BIT TOWARDS THE ENSEMBLE 
TEMPS. SEEMS REASONABLE GIVEN THE FACT THAT ALTERATIONS IN THE UPPER 
AIR PATTERN FROM RUN-TO-RUN ARE CLOSE TO THE SAME MAGNITUDE AS MEAN 
MEMBERS THEMSELVES.

&&

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

$$

MCLANE/GEOGERIAN