Drought in Tennessee, February 1 to 28, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1124 PM CST MON JAN 31 2011

.UPDATE...FOR AVIATION.

&&

.AVIATION...06Z TAFS.

VARIABLE CIGS AND VSBYS ACROSS THE AREA LEAD TO LOW CONFIDENCE ON
SPECIFIC CATEGORIES OVERNIGHT...EXPECT SEVERAL AMENDMENTS.

THROUGH THIS TAF PERIOD...A DEVELOPING LOW PRESSURE SYSTEM WILL
MOVE OVER THE LOWER MS VALLEY...FEEDING MOIST AIR ACROSS A WARM
FRONTAL ZONE. WIDESPREAD MVFR CIGS/VSBYS CAN BE EXPECTED WITH CIGS
DROPPING TO IFR AT TIMES THROUGH 15Z. THE LOW PRESSURE WILL MOVE
CLOSER CAUSING GUSTY WINDS OVER 30 KT BY 18Z. +TSRA WITH PERIODS
OF IFR AND GUSTS OVER 35 KT WILL DEVELOP AROUND 20Z AT BNA...23Z
AT CSV. FROPA EXPECTED AT BNA AROUND 03Z WITH IMPROVING
VSBYS...BUT VERY GUSTY WINDS.

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&&

.PREV DISCUSSION... /ISSUED 946 PM CST MON JAN 31 2011/

UPDATE...
WITH NO APPARENT SIGNIFICANT TRIGGER FOR LIGHT RAINFALL THRU MUCH
OF THE REMAINDER OF TONIGHT...WILL CUT RAINFALL CHANCES BACK TO
SLIGHT FOR THE TONIGHT PERIOD ALSO. OTHERWISE...FORECAST AND
BELOW FORECAST REASONING REMAINS ON TRACK. NEW 00Z GFS/NAM MODEL
RUN SOLUTIONS CONTINUING TO SHOW A TIGHT SFC PRESSURE GRADIENT
POTENTIAL STARTING TUE AFTERNOON AND CONTINUING THRU TUE NIGHT...
AND THUS WILL CONTINUE WIND ADVISORY ACROSS THE MID STATE DURING
THIS TIME PERIOD. WILL REFRESH...IF NEEDED...AND SEND OUT UPDATE
TO WIND ADVISORY BY TOP OF THE HOUR.

PREV DISCUSSION.../ISSUED 318 PM CST MON JAN 31 2011/

DISCUSSION...
WARM FRONT PUSHING NORTHWARD ACROSS MIDDLE TN AT THIS TIME. TEMPS IN
THE 50S ARE NOW COMMON AS FAR NORTH AS WILLIAMSON COUNTY WHILE NEAR
40 TEMPS REMAIN ACROSS THE TN/KY BORDER. NOT MUCH PRECIP TO SPEAK
OF...JUST A FEW SHOWERS ACROSS THE FAR NORTHERN PLATEAU.

THE WARM AIR SHOULD WIN OUT OVERNIGHT AS THE WARM FRONT PUSHES NORTH
OF THE MID STATE. TEMP FORECASTING WILL BE RATHER DIFFICULT
OVERNIGHT AS ONLY MINIMAL DIURNAL COOLING IS EXPECTED. PRECIP
WISE...SCT LIGHT RAIN SHOWERS WILL BE AN ONGOING POSSIBILITY.
BUT...DYNAMICS LOOK WEAK SO I WILL UNDERCUT THE PRECIP GUIDANCE.

ON TUESDAY...UPPER TROUGH AXIS TO STRENGTHEN OVER THE PLAINS AND
BECOME MORE NEGATIVELY TILTED. THIS WILL TRANSLATE INTO GOOD
CYCLOGENESIS WITH A SFC LOW EXPECTED TO TRACK FROM HOUSTON THROUGH
MEMPHIS BY 00Z WED. GRADIENT TO REALLY TIGHTEN UP DURING THE DAY AND
WE ARE STILL SCHEDULED TO REACH WIND ADVISORY CRITERIA BY MID
AFTERNOON. WIND SPEEDS WILL INCREASE THROUGH THE EVENING WITH 35KT
TO 40KT GUSTS COMMONPLACE ACROSS THE AREA.

AS FOR THE PRECIP...IT LOOKS AS THOUGH THE HEAVIER SHOWERS AND TSTMS
WILL HOLD OFF UNTIL TUESDAY AFTERNOON. THE ACTUALLY FRONTAL BOUNDARY
WILL MOVE THROUGH WED EVENING. THE HEAVIEST RAINFALL WILL BE OVER
WESTERN TN WHERE THE ACTUAL PASSAGE OF THE SFC LOW OCCURS. STILL
THOUGH...ONE HALF TO 1 INCH RAINFALL AMOUNTS CAN BE EXPECTED WEST
OF THE PLATEAU...WITH ONE QUARTER TO ONE HALF INCHES FOR THE PLATEAU.
AS FOR ANY SEVERE THREAT...COULD SEE SOME ISOL SEVERE ACROSS THE
WESTERN QUARTER OF THE AREA AS THE 850 MB JET REACHES 75 KTS - 80
KTS AND SHOWALTER VALUES FALL TO ZERO. OTW...INSTABILITY DOES NOT
LOOK STRONG ENOUGH AT THIS TIME FOR A MORE WIDESPREAD SEVERE EVENT.

TEMPS WILL DROP RAPIDLY BEHIND THE COLD FRONT. TUESDAY EVENING TEMPS
IN THE 50S WILL DROP DOWN INTO THE UPPER 20S TO NEAR 30 BY WEDNESDAY
MORNING. WIND SPEEDS BY SUNRISE WED MORNING WILL DECREASE.
BUT...WITH A 15 TO 20 MPH WIND...WIND CHILL VALUES IN THE TEENS CAN
BE EXPECTED AT THE BUS STOPS FOR WED MORNING.

A FEW FLURRIES WILL CONTINUE ACROSS THE NORTHEAST HALF OF THE MID
STATE FOR LATE TUESDAY NIGHT AND EARLY WED MORNING. 850 MB MOISTURE
REALLY DECREASE PRIOR TO THE ARRIVAL OF THE COLD AIR LATE TUESDAY
NIGHT. THUS...I AM NOT EXPECTING MUCH MORE THAN FLURRIES AS THE
COLDER AIR WORKS IN....PERHAPS A FEW SNOW SHOWERS FOR OUR PLATEAU.

IN THE EXTENDED FCST...SFC HIGH BUILDS IN AND MODERATES THU AND
FRIDAY. AT THE SAME TIME...STORM SYSTEM DEVELOPS OVER THE GULF AND
MOVES ACROSS FL. MOISTURE WILL SPREAD NORTHWARD BUT ITS UNCERTAIN AS
TO HOW FAR NORTH THE MOISTURE WILL GET. UPPER SUPPORT WILL THEN
SWING THROUGH OVER THE WEEKEND AND PROVIDE A CONTINUING CHANCE OF
RAIN OR SNOW. BEST CHANCE OF RAIN OR SNOW APPEARS TO BE FRIDAY AND
FRIDAY NT AS THE BETTER UPPER ENERGY REACHES THE AREA.

WARMER WEATHER EXPECTED FROM SUNDAY AND MONDAY WITH A CHANCE OF RAIN
RETURNING. THEN...COLD WEATHER TO RETURN ONCE AGAIN FOR DAYS 8-10.

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&&

.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 6 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
TNZ008>011-028>034-062>066-075-077>080.

WIND ADVISORY FROM 3 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
TNZ005>007-022>027-056>061-093>095.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NASHVILLE TN
545 PM CST MON JAN 31 2011

TNZ008>011-028>034-062>066-075-077>080-011100-
SUMNER-MACON-CLAY-PICKETT-WILSON-TROUSDALE-SMITH-JACKSON-PUTNAM-
OVERTON-FENTRESS-RUTHERFORD-CANNON-DE KALB-WHITE-CUMBERLAND-
BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-
545 PM CST MON JAN 31 2011

...WIND ADVISORY IN EFFECT FROM 6 PM TUESDAY TO 6 AM CST
WEDNESDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

...WIND ADVISORY IN EFFECT FOR LATE TUESDAY AFTERNOON AND
TUESDAY NIGHT...

STRONG LOW PRESSURE INFLUENCES WILL MOVE INTO THE AREA TUESDAY
AFTERNOON AND EVENING. STRONG SOUTHERLY WINDS ARE EXPECTED
IN ADVANCE OF THIS SURFACE LOW PRESSURE SYSTEM. SUSTAINED
SOUTHWEST WINDS 20 TO 30 MPH WITH GUSTS UP TO 40 MPH WILL
ALSO BE POSSIBLE. WARM MOIST AIR AND STRONG LOW LEVEL WINDS
COULD ALSO PRODUCE ISOLATED SEVERE THUNDERSTORMS.

AS A RESULT...SOME SHALLOW ROOTED TREES MAY BE BLOWN OVER.
LOOSE ITEMS LIKE PATIO FURNITURE AND GARBAGE CANS MAY ALSO BE
BLOWN AROUND. ANY HIGH PROFILE VEHICLES SHOULD EXERCISE CAUTION.
AFTER THE COLD FRONT PASSES TUESDAY NIGHT...TEMPERATURES WILL
DROP RAPIDLY BEHIND THE FRONT. HIGH TEMPERATURES FOR WEDNESDAY
WILL ONLY BE IN THE MID 30S.

MORE INFORMATION IS AVAILABLE ON THE INTERNET AT WEATHER.GOV OR
BY LISTENING TO NOAA WEATHER RADIO.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS AND LOCAL EMERGENCY MANAGEMENT OFFICIALS ARE ENCOURAGED
TO REPORT HIGH WINDS...ESPECIALLY THOSE THAT CAUSE DAMAGE...TO
THE NATIONAL WEATHER SERVICE IN NASHVILLE.

TNZ005>007-022>027-056>061-093>095-011100-
STEWART-MONTGOMERY-ROBERTSON-BENTON-HOUSTON-HUMPHREYS-DICKSON-
CHEATHAM-DAVIDSON-PERRY-HICKMAN-LEWIS-WILLIAMSON-MAURY-MARSHALL-
WAYNE-LAWRENCE-GILES-
545 PM CST MON JAN 31 2011

...WIND ADVISORY IN EFFECT FROM 3 PM TUESDAY TO 6 AM CST
WEDNESDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

STRONG LOW PRESSURE INFLUENCES WILL MOVE INTO THE AREA TUESDAY
AFTERNOON AND EVENING. STRONG SOUTHERLY WINDS ARE EXPECTED
IN ADVANCE OF THIS SURFACE LOW PRESSURE SYSTEM. SUSTAINED
SOUTHWEST WINDS 20 TO 30 MPH WITH GUSTS UP TO 40 MPH WILL
ALSO BE POSSIBLE. WARM MOIST AIR AND STRONG LOW LEVEL WINDS
COULD ALSO PRODUCE ISOLATED SEVERE THUNDERSTORMS.

AS A RESULT...SOME SHALLOW ROOTED TREES MAY BE BLOWN OVER.
LOOSE ITEMS LIKE PATIO FURNITURE AND GARBAGE CANS MAY ALSO BE
BLOWN AROUND. ANY HIGH PROFILE VEHICLES SHOULD EXERCISE CAUTION.
AFTER THE COLD FRONT PASSES TUESDAY NIGHT...TEMPERATURES WILL
DROP RAPIDLY BEHIND THE FRONT. HIGH TEMPERATURES FOR WEDNESDAY
WILL ONLY BE IN THE MID 30S.

MORE INFORMATION IS AVAILABLE ON THE INTERNET AT WEATHER.GOV OR
BY LISTENING TO NOAA WEATHER RADIO.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS AND LOCAL EMERGENCY MANAGEMENT OFFICIALS ARE ENCOURAGED
TO REPORT HIGH WINDS...ESPECIALLY THOSE THAT CAUSE DAMAGE...TO
THE NATIONAL WEATHER SERVICE IN NASHVILLE.

SPOTTER THUNDERSTORM REPORTING CRITERIA...
TORNADO
FUNNEL CLOUD
FLOODING
HAIL >= 1/2 INCH
WINDS > 50 MPH (MEASURED)
STRUCTURAL DAMAGE
TREES OR POWER LINES DOWN

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