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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS63 KJKL 050640 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON KY
140 AM EST THU DEC 5 2013

.UPDATE...
-- Changed Discussion --
ISSUED AT 140 AM EST THU DEC 5 2013

FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO MATCH THE
CURRENT OBSERVATIONS. A FEW SHELTERED VALLEYS HAVE MANAGED TO
DECOUPLE AND ARE CURRENTLY REPORTING IN THE LOW TO MID 50S. MOST
OTHER LOCATIONS ARE IN THE 60S. EXPECT THE DEEPER VALLEYS TO
EVENTUALLY MIX OUT AS CLOUDS THICKEN AND THE SURFACE PRESSURE
GRADIENT INCREASES ACROSS THE AREA. A LINE OF PRECIPITATION IS ALSO
STARTING TO FIRE UP FROM SOUTHWEST INDIANA DOWN THROUGH WESTERN
KENTUCKY. THE CURRENT POPS SEEM REASONABLE AS IT WILL TAKE SOME TIME
FOR THE BETTER MOISTURE CONVERGENCE TO ADVECT IN FROM THE WEST.

UPDATE ISSUED AT 1041 PM EST WED DEC 4 2013

UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
BLENDS. ONLY MADE SOME MINOR TWEAKS. THE TEMPS HAVE NOT BEEN DROPPING
AS FAST AS FORECAST...SO HAD TO RAISE THE MIN TEMP UP A LITTLE. THE
LOW TEMPERATURE TONIGHT WILL HAVE A GOOD CHANCE TO BREAK THE RECORD
HIGHEST LOW TEMPERATURE FOR DEC 5TH. THE REST OF THE FORECAST IS ON
TRACK. NO NEW ZONE FORECASTS WILL BE ISSUED...HOWEVER THE INTERNET
AND NDFD HAVE BEEN UPDATED.

UPDATE ISSUED AT 657 PM EST WED DEC 4 2013

UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL
BLENDS. ONLY MADE SOME MINOR TWEAKS. THE REST OF THE FORECAST IS ON
TRACK. NO NEW ZONE FORECASTS WILL BE ISSUED...HOWEVER THE INTERNET
AND NDFD HAVE BEEN UPDATED.
-- End Changed Discussion --

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 351 PM EST WED DEC 4 2013

HAVE DECIDED TO ISSUE A FLOOD WATCH BEGINNING THURSDAY EVENING AND
CONTINUING THROUGH SATURDAY MORNING. FOR THE SHORT TERM PORTION OF
THE FORECAST ALL PRECIPITATION WILL BE IN THE FORM OF RAIN...WITH
SOME LOCALLY HEAVY RAIN POSSIBLE BEGINNING THURSDAY NIGHT. WITH
PRECIPITABLE WATER FORECAST IN EXCESS OF 1.5 INCHES OR THE 99TH
PERCENTILE...HEAVY RAINS DEFINITELY A MAJOR CONCERN. THROUGH
THURSDAY NIGHT EXPECTING MOST AREAS TO RECEIVE IN EXCESS OF AN INCH
OF RAIN...WITH ADDITIONAL RAIN OCCURRING ON FRIDAY.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 612 PM EST WED DEC 4 2013

WHAT A FORECAST PERIOD. MODELS ARE IN RELATIVELY GOOD AGREEMENT
CONSIDERING THE COMPLEXITY OF THE FORECAST. HAVE USED A GFS/NAM BLEND
IN THE EARLY SECTION TO ADDRESS MOST DIFFERENCES. CONCERNS CENTER ON
BOTH THE THREAT OF HEAVY RAINFALL AND WINTER WEATHER THROUGH SUNDAY.

A QUASI-STATIONARY FRONT WILL BE SITUATED JUST TO OUR SE TO START THE
PERIOD...WITH A VERY LARGE AREA OF SOUTHWESTERLY FLOW ALOFT ON THE SE
SIDE OF A MASSIVE LONG WAVE TROUGH OVER THE CONTINENT. OVERRUNNING
PRECIP WILL BE ONGOING TO START FRIDAY MORNING. STRONG WARM/MOIST
ADVECTION ALOFT MAY EVEN SUPPLY WEAK INSTABILITY FOR SOME
THUNDERSTORMS ON FRIDAY. MEANWHILE...AT THE SURFACE...COLDER AIR WILL
BE ARRIVING FROM THE NORTH. THIS WILL RESULT IN RAIN CHANGING TO A
WINTERY MIX IN OUR FAR NORTHWEST DURING FRIDAY AFTERNOON...WITH THE
TRANSITION MARCHING SE DURING FRIDAY NIGHT AS PRECIP BEGINS TO TAPER
OFF. AS A RESULT...THE GREATEST THREAT OF PROBLEMS FROM WINTERY
WEATHER ON FRIDAY INTO FRIDAY NIGHT WILL BE IN OUR NW. BASED ON THE
CURRENT FORECAST...A WINTER WEATHER ADVISORY WOULD EVENTUALLY BE
NEEDED. IT WOULD NOT TAKE MUCH CHANGE TO WARRANT A WINTER STORM
WATCH OR EVENTUAL WARNING IN OUR NW...BUT OPTED TO HOLD OFF ON A
WATCH. STRONG FORCING AND THE POSSIBILITY OF EMBEDDED CONVECTION
COULD SPELL FLOODING PROBLEMS...AND A FLOOD WATCH WAS ISSUED IN
COLLABORATION WITH RLX TO THE EAST. IF PROBLEMS DO NOT ARISE BY
FRIDAY NIGHT...A LIKELY SCENARIO IS FOR RAINFALL THROUGH FRIDAY NIGHT
TO BRING SIGNIFICANT RISES ON STREAMS AND PRIME US FOR PROBLEMS WITH
ANOTHER ROUND OF PRECIP DURING THE WEEKEND. AS DEEP MOISTURE IS LOST
ON FRIDAY NIGHT AND COLDER AIR CONTINUES TO ARRIVE...ANY REMAINING
PRECIP SHOULD TAPER TO AREAS OF FREEZING DRIZZLE...WHICH THEN TAPERS
OFF ON SATURDAY.

AFTER A LULL IN PRECIP SATURDAY AFTERNOON...ROUND NUMBER TWO WILL
ARRIVE SATURDAY NIGHT. LOW PRESSURE IS FORECAST TO DEVELOP AND MOVE
NNW FROM THE GULF OF MEXICO IN RESPONSE TO A STRONG IMPULSE IN THE
TROUGH ALOFT. THIS DRAW MILDER AIR BACK NORTH OVER THE LOCAL
AREA...WITH STRONG WARM/MOIST ADVECTION ALOFT DEVELOPING AGAIN.
INITIAL PRECIP LOOKS LIKE IT WILL BEGIN AS A WINTERY MIX AND THEN
CHANGE OVER TO RAIN FROM SOUTH TO NORTH...WITH EVERYPLACE GOING OVER
TO PLAIN RAIN ON SUNDAY. THIS COULD BE ENOUGH TO SEND STREAMS INTO
FLOOD...AND ANOTHER FLOOD WATCH MAY BE NEEDED. DEEP MOISTURE PULLS
OUT TO THE EAST LATE SUNDAY NIGHT AND EARLY MONDAY...PUTTING AN END
TO THE HEAVY RAIN POTENTIAL.

ONCE THIS SYSTEM PASSES BY...MUCH COLDER AIR WILL ARRIVE. AS THE TOP
OF THE LOW LEVEL MIXED LAYER COOLS TO -10C...WE MAY SEE SNOW SHOWERS
MONDAY NIGHT INTO TUESDAY. THIS COULD BE FOLLOWED BY SOME OF THE
COLDEST TEMPERATURES OF THE SEASON SO FAR.

&&

.AVIATION...
-- Changed Discussion --
(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EST THU DEC 5 2013

WILL KEEP VFR CONDITIONS IN PLACE THROUGH 12Z ACROSS THE AREA. CLOUDS
WILL THICKEN AND LOWER WITH TIME...WITH AN AMPLE LOW LEVEL JET
PROVIDING SOME LOW LEVEL WIND SHEAR ALONG AND EAST OF I-75 THROUGH
12Z. RAIN SHOWERS WILL BEGIN TO THREATEN TOWARDS DAWN...WITH MORE
WIDESPREAD ACTIVITY GRADUALLY MOVING IN FROM WEST TO EAST THROUGH THE
AFTERNOON AS A COLD FRONT MOVES SOUTHEAST ACROSS THE AREA. CEILINGS
WILL GRADUALLY LOWER TO IFR AS STEADY RAINS CONTINUE TONIGHT. SOUTH
WINDS AT 5 TO 10 KTS...WITH SOME GUSTS UP TO 15 KTS WEST OF I-75 AND
ALONG AND NORTH OF I-64...WILL PREVAIL THROUGH DAWN. WINDS WILL
GRADUALLY VEER TO THE SOUTHWEST DURING THE DAY...AND THEN SHIFT TO
THE NORTHWEST BEHIND THE COLD FRONT.
-- End Changed Discussion --

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
FLOOD WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120.
-- End Changed Discussion --

&&

$$

UPDATE...GEOGERIAN
SHORT TERM...SBH
LONG TERM...HAL
AVIATION...GEOGERIAN