FXUS64 KOHX 260328
AFDOHX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
928 PM CST WED NOV 25 2009

.UPDATE...
LOOKS LIKE CLEAR SKIES OVER SOUTHEASTERN MIDDLE TN ARE ALLOWING TEMPS
TO FALL QUICKER THAN PREVIOUSLY FORECAST IN THAT AREA WHILE SCATTERED
TO BROKEN STRATOCUMULUS ACROSS NORTHERN AREAS ARE HOLDING TEMPS
UP. WILL UPDATE AND LOWER OVERNIGHT MINS IN SOUTHEAST MIDDLE TN
INTO THE LOW TO MIDDLE 30S. I LOOK FOR CLOUDS TO INCREASE OVERNIGHT
ESPECIALLY NORTHERN AREAS OF MID STATE. IF THIS HAPPENS OVERNIGHT
MINS ACROSS NORTHERN AREAS COULD BE WARMER THAN CURRENTLY FORECAST.

WILL UPDATE CURRENT GRIDS/ZONES FOR TEMP TWEAKS OVER SOUTHEAST
MIDDLE TN. MAY NEED TO UPDATE CLOSER TO SHIFT CHANGE DEPENDING ON
CLOUDS AND TEMP TRENDS ACROSS NORTHERN AREAS.

BOYD

&&

.PREV DISCUSSION... /ISSUED 345 PM CST WED NOV 25 2009/ 

DISCUSSION...
FORECAST REASONING WILL BE BASED ON A LEAN TOWARD A EURO SOLUTION FOR
THE FORECAST PERIOD UNLESS OTHERWISE NOTED.

CURRENTLY...A FEW PATCHES OF STRATO-CU NOTED...OTHERWISE CLEAR 
SKIES. TEMPS MAINLY IN THE MID TO UPPER 50S...DEWPOINTS MAINLY
IN THE MID 30S...WITH W TO SW SFC WINDS OF AROUND 10 MPH.
SFC LOW ACROSS UPPER LAKE MI AND SFC HIGH ACROSS SW GA. LOW LEVEL
TROUGHING REMAINING ACROSS W TN. SUBTLE SWLY FLOW ALOFT IN BASE
OF UPPER LEVEL TROUGH WITH UPPER LEVEL LOW POSITIONED ACROSS
CNTRL IA. OF PARTICULAR NOTE...CLOUDINESS NOTED ACROSS S IL INTO
SW MO OZARKS. 

FORECAST QUANDARIES...FOR TONIGHT...ONE QUANDARY CENTERS AROUND THE
POSSIBILITY OF THE ISSUANCE OF A FROST ADVISORY OR FREEZE WARNING
FOR AREAS W OF THE CUMBERLAND PLATEAU. LOCAL CRITERIA STATES THAT
CONTINUED ISSUANCE OF THESE PRODUCTS FOR AREAS THAT HAVE NOT 
EXPERIENCED A KILLING FREEZE...TEMPS EQUAL TO OR LESS THAN 27 
DEGREES...THRU NOV. 30TH. CLOUDS PRESENTLY ACROSS S IL INTO SW MO 
OZARKS ARE EXPECTED TO MOVE ACROSS THE MID STATE AFTER MIDNIGHT 
TONIGHT IN ASSOCIATION WITH A SHORTWAVE PASSAGE AROUND THE BASE OF A 
DEEPENING UPPER LEVEL TROUGH ASSOCIATED WITH AN UPPER LEVEL LOW 
MOVING NEWD INTO N INDIANA BY AROUND 12Z THU. THERE MIGHT BE SOME 
CLEARING BEHIND THIS PASSAGE...BUT AT THIS TIME...EVEN WITH TEMPS 
POSSIBLY FALLING INTO THE FROST ADVISORY WINDOW...33 TO 36 DEGREES
..WINDS SHOULD BE IN THE 5 TO 10 MPH RANGE AND NOT DECOUPLE FROM
THE BOUNDARY LAYER. WITH THIS IN MIND...GFS MOS VALUES SEEMS TO
HANDLE THIS SCENARIO WELL...AND WILL LEAN ACCORDINGLY.

ENHANCED COOLING STARTS TO PUSH IN ON THANKSGIVING DAY...AS A STRONG
SECONDARY COLD FRONT SWEEPS IN AND BRINGS A SWATH OF STRATOCU INTO
THE AREA AND MOCLDY CONDITIONS BY TURKEY DAY SUNSET. THERE WILL ALSO
BE AT LEAST A SMALL CHANCE FOR SHWRS BY THE AFTERNOON...ESPECIALLY
OVER THE N AND E. SOME ERN AREAS COULD SEE A FEW FLAKES OF SNOW MIX
IN WITH THE RAIN THU NIGHT...AS COLDER AIR CONTINUES TO MOVE IN AND
INTERACT WITH LINGERING ATMOSPHERIC MOISTURE. WILL GO CLOSE TO GFS
MOS ON HIGHS AND FOR LOWS...LOOK FOR THEM TO BE IN THE LOW TO MID
30S...SO A FREEZE WARNING MAY BE POSSIBLE FOR THU NIGHT. WITH THIS
IN MIND...WILL ISSUE A FREEZE WATCH FOR AREAS W OF CUMBERLAND PLATEAU
FOR THU NIGHT.   

CLOUDS PULL E OF THE MID STATE ON FRI...ALLOWING FOR A DRY AND COOL 
WEEKEND TO SETTLE IN...AS RIDGING SFC AND ALOFT MOVE INTO THE 
REGION. EXPECT LOWS IN THE 30S OVER MOST OF THE MID STATE BOTH 
SAT AND SUN MORNING. DAYTIME HIGHS WILL BE MAINLY IN THE 50S.

ANOTHER TROUGH APPROACHES THE AREA EARLY NEXT WEEK AND SAGS SLOWLY 
SEWD ACROSS THE MID STATE. HAVE GONE CLOSELY WITH THE EURO...PUSHING
A COLD FRONT THRU THE MID STATE ON MON. AREA WILL LIKELY SEE A
GOOD BAND OF POST-FRONTAL ISENTROPIC CLOUDS LINGERING INTO TUE AND
TUE NIGHT. A WAVE MAY DEVELOP ON THE FRONT AND SWING BACK TO THE
NW ONTO THE CUMBERLAND PLATEAU TUE NIGHT. COLD AIR WILL GRADUALLY
SINK SWD OVER AT LEAST THE WRN TWO-THIRDS OF THE MID STATE MON
NIGHT THROUGH TUE NIGHT...AND HAVE CONTINUED TO MAKE SIGNIFICANT
ADJUSTMENTS TO GFS MOS NUMBERS LIKE MORNING FORECAST ISSUANCE.
AS THE COLD AIR MOVES...THE NW PORTIONS OF THE MID STATE MAY SEE
A PERIOD OF MIXED PRECIPITATION MON NIGHT AND TUE...AND WILL
CONTINUE TO CONFINE POSSIBILITY TO NW COUNTIES ONLY.

A RETURN TO HIGH PRESSURE AND DRY CONDITIONS IS EXPECTED BY THE 
MIDDLE OF NEXT WEEK...WITH NEXT FRONTAL SYSTEM MOVING INTO THE
MID STATE BY EARLY NEXT WEEKEND.

THANKS FOR COORDINATION HUN AND MEG. 

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR 
TNZ005>009-022>030-056>064-075-077-093>095.

&&

$$

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