Special Weather Statement, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
412 AM CST FRI MAR 2 2012

WARM FRONT CURRENTLY LIFTING NORTHWARD ACROSS THE MID STATE.
DEWPOINT GRADIENT IS QUITE IMPRESSIVE WITH 36F AT BNA AND 62F AT HSV
AT 2 AM. WEAK SPEED CONVERGENCE WILL ACCOMPANY THE WARM FRONT
PASSAGE. THUS...A FEW SHOWERS WILL SPREAD NORTHWARD THIS MORNING.

DURING THE DAY TODAY...PROG SOUNDINGS SHOWING VERY DRY AIR FROM
700MB UPWARD THROUGH MUCH OF THE DAY. MEANWHILE...LOWER LEVELS WILL
BECOME INCREASINGLY UNSTABLE. WITH THE OVERALL AIRMASS DEPTH BEING
ON THE DRY SIDE...IT LOOKS AS THOUGH MORE IN THE WAY OF SCATTERED
CONVECTION CAN BE EXPECTED THROUGH THE MORNING AND EARLY AFTERNOON.
THEN...AS WE WARM UP...THE ADDED INSTABILITY WILL WORK IN FAVOR OF
MORE LINEAR AND ORGANIZED CONVECTION. THE POSITIONING OF THE COLD
FRONT LOOKS AS THOUGH IT WILL MOVE THROUGH THE NASHVILLE AREA AROUND
7 OR 8 PM TONIGHT. MUCH OF THE FORCING WILL RESIDE A FEW HOURS AHEAD
OF THE FROPA. SUMMING THIS ALL TOGETHER...IT LOOKS TO ME AS THOUGH
SCATTERED CONVECTION WILL OCCUR ACROSS MIDDLE TN THIS MORNING AND
INTO THE EARLY AFTERNOON. THEN...COVERAGE WILL INCREASE ACROSS
EASTERN ZONES IN THE AFTERNOON AS THE CAP BUSTS. MY POPS FOR TODAY
WILL RANGE FROM 50 ACROSS THE WEST TO 70 PLATEAU. I WILL LEAN
HEAVILY TOWARD ISC GRIDS AND ADJUST ACCORDINGLY.

AS FOR THE SEVERE POTENTIAL...WITH TEMPS EXPECTING TO WARM UP TO
NEAR 80 FOR MUCH OF THE AREA WEST OF THE PLATEAU...INSTABILITIES IN
THE LOWER LEVELS WILL INCREASE QUITE SUFFICIENTLY TO SUPPORT THE
SEVERE STORM DEVELOPMENT. FURTHERMORE...50-55 KT LOW LEVEL JET WITH
0-3KM HELICITY VALUES AROUND 250 - 300 IN THE LATE AFTERNOON WILL
PROVIDE AMPLE LOW LEVEL SHEAR. WILL THEREFORE INCLUDE THE MENTION OF
SEVERE STORMS IN THE FCST...WITH AFT WORDING USED...LATE AFT/EARLY
EVE PLATEAU. VERY LOW LCL LEVELS WILL SUPPORT ISOLATED TORNADIC
CONDITIONS.

AGAIN...AT THIS POINT IN TIME...THE TIMING OF THE SEVERE WEATHER
LOOKS AS THOUGH IT WILL OCCUR FROM NOON-4PM WEST...2P-6P
CENTRAL...AND 4P-8P FOR THE EASTERN PLATEAU. SCT SEVERE CONVECTION
WEST...WITH LINEAR FORMATION AND BETTER ORGANIZATION ACROSS OUR EAST
AS WE GAIN ADDITIONAL HEATING.

OTHERWISE...TIGHT GRADIENT TODAY WITH WIND ADVISORY CRITERIA ALONG
OUR WESTERN QUARTER. WILL GO AHEAD AND INCLUDE A WIND ADVISORY FOR
THAT AREA.

AFTER TONIGHT'S FROPA....COOLER AND MORE SEASONAL WEATHER WILL
RETURN. A QUICK MOVING DISTURBANCE WITH THE NW FLOW WILL BRING A
CHANCE OF SHOWERS FOR SUNDAY.

FOR THE NEAR TERM TEMPS...WILL UNDERCUT THE MAV HIGH TEMPS THROUGH
SUNDAY BY A FEW DEGREES.

IN THE EXT FCST...WE WILL HAVE DRY WEATHER WITH A WARMING TREND AS
WEAK UPPER RIDGING DOMINATES. NEXT STORM SYSTEM WILL NOT EFFECT THE
AREA UNTIL NEXT WEEKEND.

AGAINST THE MEX GUIDANCE...I WILL INCLUDE A SLIGHT UNDERCUT FOR THE
FIRST HALF OF THE EXTENDED.

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      79  38  56  33 /  60  60  10  10
CLARKSVILLE    78  35  53  31 /  50  40  10  10
CROSSVILLE     72  36  50  29 /  70  70  10  10
COLUMBIA       79  39  57  33 /  60  60  10  10
LAWRENCEBURG   78  39  56  32 /  60  60  10  10
WAVERLY        78  37  55  32 /  50  40  10  10

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 9 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR TNZ005-006-022>025-056>058-093-094.

&&

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
500 AM CST FRI MAR 2 2012

TNZ005>011-022>034-056>066-075-077>080-093>095-031000-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
500 AM CST FRI MAR 2 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR ALL OF
MIDDLE TENNESSEE TODAY AND TONIGHT...WITH THE BEST CHANCE OF
SEVERE THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS.
MAIN THREATS WITH SEVERE THUNDERSTORMS THAT DEVELOP WILL BE
DAMAGING WINDS...LARGE HAIL...AND STRONG...LONG TRACK TORNADOES.

A WIND ADVISORY WILL ALSO BE IN EFFECT FOR LOCATIONS GENERALLY
ALONG AND WEST OF A CLARKSVILLE...TO CENTERVILLE...TO LAWRENCEBURG
LINE FROM THE MID MORNING HOURS TODAY THROUGH THE AFTERNOON.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...

REPORTS FROM TRAINED WEATHER SPOTTERS WILL LIKELY BE NEEDED.

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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SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
324 AM CST FRI MAR 2 2012

TNZ005>011-022>034-056>066-075-077>080-093>095-030000-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
INCLUDING THE CITIES OF...DOVER...CLARKSVILLE...SPRINGFIELD...
GALLATIN...LAFAYETTE...CELINA...BYRDSTOWN...CAMDEN...ERIN...
WAVERLY...DICKSON...ASHLAND CITY...NASHVILLE...LEBANON...
MOUNT JULIET...HARTSVILLE...CARTHAGE...GAINESBORO...COOKEVILLE...
LIVINGSTON...JAMESTOWN...LOBELVILLE...CENTERVILLE...HOHENWALD...
FRANKLIN...BRENTWOOD...COLUMBIA...LEWISBURG...MURFREESBORO...
WOODBURY...SMITHVILLE...SPARTA...CROSSVILLE...SHELBYVILLE...
TULLAHOMA...MANCHESTER...MCMINNVILLE...ALTAMONT...SPENCER...
WAYNESBORO...LAWRENCEBURG...PULASKI
324 AM CST FRI MAR 2 2012

...A SIGNIFICANT SEVERE WEATHER OUTBREAK WILL BE POSSIBLE ACROSS
MIDDLE TENNESSEE TODAY AND DURING THE EVENING HOURS TONIGHT...
...A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS ALL OF MIDDLE
TENNESSEE TODAY AND TONIGHT...
...MAIN THREATS WILL BE DAMAGING WINDS...LARGE HAIL...AND POSSIBLY
STRONG LONG TRACKED TORNADOES...

A STRONG LOW PRESSURE CENTER WILL PUSH NORTHEASTWARD THROUGH THE
MID MISSISSIPPI VALLEY TODAY AND TONIGHT. A STRONG COLD FRONT
WILL PUSH THROUGH THE MID STATE DURING THE LATE AFTERNOON HOURS
ACROSS WESTERN PORTIONS AND INTO THE EVENING HOURS ACROSS EASTERN
PORTIONS OF MIDDLE TENNESSEE. ALONG AND AHEAD OF THIS FRONTAL
PASSAGE...ATMOSPHERIC CONDITIONS WILL BECOME VERY FAVORABLE FOR
SEVERE THUNDERSTORM DEVELOPMENT.

LOWER LEVEL ATMOSPHERIC WINDS WILL STRENGTHEN SIGNIFICANTLY
THROUGHOUT THE DAY...WITH A WARM FRONT MOVING WELL NORTH OF THE
ENTIRE AREA BY THIS AFTERNOON. THIS WILL ALLOW FOR A MUCH WARMER
AND MOISTURE RICH AIRMASS TO BE ESTABLISHED ACROSS THE MID STATE
BY THE AFTERNOON HOURS. NEAR RECORD HIGHS WILL BE POSSIBLE FOR
MANY LOCATIONS ACROSS THE AREA. BREAKS IN CLOUD COVERAGE TODAY
WILL ALLOW FOR DAYTIME HEATING TO AID WITH ATMOSPHERIC INSTABILITY
AND LIFT. ADDITIONAL INSTABILITY AND LIFT WILL BE PROVIDED BY THE
APPROACHING STRONG COLD FRONT. THUS...ALL THE INGREDIENTS NEEDED
FOR CONVECTIVE DEVELOPMENT ON A LARGE SCALE WILL BE IN
PLACE...MOISTURE...INSTABILITY...AND LIFT. THE BEST OVERALL TIME
FOR SEVERE WEATHER POTENTIAL ACROSS THE MID STATE WILL BE FROM
NOON IN WESTERN LOCATIONS TO MID EVENING IN EASTERN LOCATIONS.

PLEASE BE SURE THAT YOUR SEVERE WEATHER SAFETY PLANS ARE IN PLACE
FOR BOTH YOUR RESIDENCE AND BUSINESS. RESIDENTS SHOULD BE SURE
THAT THEY HAVE ACCESS TO A RELIABLE SOURCE OF WEATHER INFORMATION
FOR TODAY AND TONIGHT...SUCH AS NOAA WEATHER RADIO AND YOUR LOCAL
MEDIA OUTLET. INFORMATION CONCERNING NOAA WEATHER RADIO
TRANSMITTERS AND THE LOCATION THAT THEY SERVE IN MIDDLE TENNESSEE
CAN BE FOUND ON THE NASHVILLE NATIONAL WEATHER SERVICE WEB
PAGE...AT WWW.WEATHER.GOV/NASHVILLE UNDER WEATHER SAFETY.

31

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
518 AM CST FRI MAR 02 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0509 AM     HAIL             6 E CAMDEN              36.06N 88.00W
03/02/2012  E0.75 INCH       BENTON             TN   PUBLIC

            HAIL REPORTED EAST OF CAMDEN

&&

21

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
600 AM CST FRI MAR 02 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0558 AM     HAIL             NASHVILLE               36.17N 86.78W
03/02/2012  E0.88 INCH       DAVIDSON           TN   TRAINED SPOTTER

            NICKEL HAIL REPORTED AT THE DOWNTOWN METRO CENTER.

&&

21

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
600 AM CST FRI MAR 2 2012

TNZ008-027-028-021215-
DAVIDSON-SUMNER-WILSON-
600 AM CST FRI MAR 2 2012

...SIGNIFICANT WEATHER ADVISORY FOR DAVIDSON...SUMNER AND WILSON
COUNTIES...

AT 600 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR NASHVILLE...MOVING NORTHEAST AT 55 MPH.

NICKEL SIZE HAIL...AND WIND GUST BETWEEN 50 AND 55 MPH ARE EXPECTED
WITH THIS STORM.

LAT...LON 3640 8646 3624 8633 3606 8675 3625 8687

31