Hail and Damaging Winds in Tennessee, April 11, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
943 AM CDT WED APR 11 2007

.UPDATE...14Z SURFACE MAP SHOWED LOW PRESSURE OVER NORTHEAST MO
WITH OCCLUDED FRONT EXTENDING INTO EASTERN AR...APPROACHING THE
MISSISSIPPI RIVER. WARM FRONT AND DEEP MOISTURE NOTED IN MS DOWN
TO THE FL PANHANDLE. OVER MID TN...A WEAKENING BAND OF
SHOWERS/STORMS WAS MOVING TOWARD THE PLATEAU. THIS BAND WAS THE
MAIN EVENT AS FAR AS RAINFALL IS CONCERNED. HOWEVER...SCATTERED
SHOWERS AND STORMS WERE DEVELOPING IN SOUTHWEST MIDDLE TN AND
MS. FORECAST SOUNDINGS INDICATE CONTINUED POTENTIAL FOR CONVECTION
OVER THE ENTIRE AREA UNTIL THE FRONT ARRIVES. SO...EVEN THOUGH THE
MAIN BAND OF RAIN HAS PASSED AREAS WEST OF I 65...ADDITIONAL
SHOWERS/STORMS WILL BE POSSIBLE INTO THE AFTERNOON. RAIN CHANCES
WILL PRETTY MUCH BE DONE BY 21Z FOR AREAS WEST OF I 65 AS COLUMN
DRIES SIGNIFICANTLY. EASTERN AREAS WILL CONTINUE TO HAVE HIGH POP
THROUGH THE DAY. WITH DAYTIME HEATING...ADDITIONAL DESTABILIZATION
MAY CAUSE SOME STORMS TO BECOME STRONG. A BRIEF STRONG GUST IS
POSSIBLE...AND WET BULB ZERO HEIGHTS SUGGEST POSSIBILITY FOR SOME
HAIL. ANY SEVERE WX WOULD BE VERY ISOLATED.

LAKE WIND ADVISORY LOOKS FINE AS SOME STATION GUSTING NEAR 30 MPH.
LOOK FOR A FEW HIGHER GUSTS ESPECIALLY EARLY AFTERNOON AS BETTER
MIXING OCCURS. LAST OB FROM PORTLAND SHOWED 37 MPH GUST.

FORECAST HAS THIS GENERAL SCENARIO COVERED...BUT WE WILL MAKE A
FEW ADJUSTMENT FOR TIMING AND WORDING.

&&

.PREV DISCUSSION... /ISSUED 325 AM CDT WED APR 11 2007/

DISCUSSION...
LATEST ANALYSIS SHOWING SFC/LL LOWS OVER WEST MO AND ACROSS WEST
AR. WARM FRONT INDICTED FROM SOUTHERN AR DOWN TO NEAR THE GULF
COAST WITH ASSOCIATED COLD FRONT DOWN INTO CENTRAL TX. ANOTHER
WEAK AXIS IS SITTING JUST NORTH OF THE TN/KY BORDER. ALOFT...
SOUTHWEST FLOW CONTINUES AS DEEP LOW OVER THE NORTHERN PLAINS
APPROACHES. GOOD MOISTURE ADVECTION OCCURRING AND INCREASING LL
CONVERGENCE / ML UVV HELPING TO SET SHOWER DEVELOPMENT IN MOTION.

CONVECTION EXPECTED TO BECOME MORE ACTIVE LATER TODAY. INSTABILITY
CURRENTLY LIMITED BUT AIRMASS WILL DESTABILIZE LATER THIS MORNING AS
STRONGER IMPULSE / SHORTWAVE WORKS INTO THE IMMEDIATE VICINITY. UVV
WILL BECOME VERY FAVORABLE TOWARD MIDDAY AS COLD FRONT MOVES IN...
ACCOMPANIED BY ML STREAK AND 100+KT UL JET. EXPECT NUMEROUS SHWRS/
TSTMS TO CONTINUE MUCH OF TODAY...ESPECIALLY EAST.

COLD FRONT EXPECTED TO BE NEAR OR JUST EAST OF CSV LATE TODAY
..WITH GOOD DRYING OVERALL BEHIND. HOWEVER...TIGHT UPPER LOW
WORKING INTO THE GREAT LAKES MAY SPIN A FEW LIGHT SHOWERS ACROSS
THE NORTH/EAST THIS EVENING.

DRY TREND WILL CONTINUE LATE TONIGHT INTO FRIDAY AFTERNOON WHEN
NEXT STORM SYSTEM BEGINS TO AFFECT THE MID-STATE. BRUNT OF NEXT
SYSTEM EXPECTED TO CROSS THE CWA FRIDAY NIGHT/SATURDAY...WHEN
SEEMINGLY STRONG TSTMS MAY BE POSSIBLE.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR TNZ005>011-
022>034-056>066-075-077>080-093>095.

&&

13

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
530 AM CDT WED APR 11 2007

TNZ005>011-022>034-056>066-075-077>080-093>095-121030-
BEDFORD-BENTON-CANNON-CHEATHAM-CLAY-COFFEE-CUMBERLAND-DAVIDSON-
DEKALB-DICKSON-FENTRESS-GILES-GRUNDY-HICKMAN-HOUSTON-HUMPHREYS-
JACKSON-LAWRENCE-LEWIS-MACON-MARSHALL-MAURY-MONTGOMERY-OVERTON-PERRY-
PICKETT-PUTNAM-ROBERTSON-RUTHERFORD-SMITH-STEWART-SUMNER-TROUSDALE-
VAN BUREN-WARREN-WAYNE-WHITE-WILLIAMSON-WILSON-
530 AM CDT WED APR 11 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

STRONG THUNDERSTORMS ARE POSSIBLE TODAY...AS A COLD FRONT MOVES
ACROSS THE AREA. A STORM OR TWO MAY EVEN REACH SEVERE LIMITS
PRODUCING DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

LATE FRIDAY NIGHT AND SATURDAY STRONG THUNDERSTORMS ARE EXPECTED
TO MOVE THROUGH THE MID-STATE. ISOLATED SEVERE THUNDERSTORMS ARE
POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

NO SPOTTER ACTIVATION IS ANTICIPATED AT THIS TIME.

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