Areal Flood Warning 1, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1235 AM CDT WED APR 27 2011

.UPDATE...FOR AVIATION.

&&

.AVIATION...06Z TAFS.

MAINLY MVFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AS
WAVES OF THUNDERSTORMS CROSS THE REGION. BRIEF IFR WILL OCCUR WITH
THE HEAVIER STORMS. PERIODS OF SEVERE WX ARE LIKELY. GUSTY SSW
WINDS WILL ALSO OCCUR.

13

&&

.PREV DISCUSSION... /ISSUED 959 PM CDT TUE APR 26 2011/

MESOSCALE UPDATE...
NEW TOR WATCH 224 WL BE ISSUED FOR A LARGE PART OF MID TN TO JUST
E OF INTERSTATE 65 UNTIL 10Z. CELLS ARE FORMING ALONG BOUNDARY IN
N MS MOVG NNE...WITH SOME CELLS ROTATING NEAR TN RIVER. LLJ IN N
MS EXPECTED TO PUSH NORTHEAST NEXT 2-4 HRS.

PREV DISCUSSION... /ISSUED 906 PM CDT TUE APR 26 2011/

MESOSCALE UPDATE...
CONCERNED FOR STORMS CURRENTLY MOVING THROUGH CHESTER AND MCNAIRY
COUNTIES IN WEST TENNESSEE AS ROTATION VERY EVIDENT IN STORM OVER
HENDERSON AT THIS TIME. STORMS STILL A WAYS OFF FROM MY CWA BUT
WILL MONITOR CLOSELY. HAVE ISSUED AN SPS ADDRESSING APPROACHING STORMS.
WE HAVE ALSO INCLUDED THE COUNTIES OF PERRY AND WAYNE IN THE
TORNADO WATCH NUMBER 217 WHICH ENDS AT 27/03Z. WE ALSO EXPECT A NEW
WATCH BOX LIKELY AFTER 27/03Z.

BOYD

PREV DISCUSSION... /ISSUED 847 PM CDT TUE APR 26 2011/

UPDATE...
SCT RW/TRW DEVELOPING IN S MID TN MOVG N. LAPS SHOWS POCKETS OF
MOD INSTAB W/SHEAR INCREASING SO A WATCH IS FORTHCOMING. LLJ IN
NORTH MS/SOUTHWEST TN EXPECTED TO PUSH EAST...WITH CLUSTER OF
STRONG TO SEVERE STORMS GETTING INTO SW MID TN NEXT 1-2 HRS.

BOYD

PREV DISCUSSION... /ISSUED 543 PM CDT TUE APR 26 2011/

MESOSCALE UPDATE...
MESO CONVECTIVE SYSTEM HAS FIRED OVER SOUTHERN ARKANSAS THIS
AFTERNOON WITH SCATTERED STRONG TO SEVERE CONVECTION ACROSS FAR
WESTERN KENTUCKY AND PARTS OF WESTERN TENNESSEE NEAR MISSISSIPPI RIVER.
A FEW STORMS IN WESTERN KY HAVE EXHIBITED SUPERCELL CHARACTERISTICS.
850-300 MILLIBAR MEAN WIND FIELD WILL DRIVE MCS UP THROUGH THE
MEMPHIS AREA AND INTO WESTERN TENNESSEE THROUGH MID-EVENING.
SURFACE BASED LIFTED INDICES ARE -8 WITH ENERGY HELICITY INDICES
3 AND 4 IN PARTS OF MID STATE THIS EVENING. EXPECT ANY ISOLATED
TO SCATTERED STORMS THAT DO FORM TO HAVE ROTATION AND BECOME SUPER
CELLS.

CURRENTLY MEAN WIND VECTOR ON STORMS IN WESTERN KY 230/40KTS.

BOYD

PREV DISCUSSION... /ISSUED 348 PM CDT TUE APR 26 2011/

SHORT TERM...A TORNADO WATCH IS IN EFFECT FOR NORTHWESTERN MIDDLE
TENNESSEE...AND SPC HAS DECLARED THIS A "PARTICULARLY DANGEROUS
SITUATION" WITH ENVIRONMENTAL CONDITIONS FAVORING THE DEVELOPMENT
OF DESTRUCTIVE TORNADOES. THUNDERSTORMS CONTINUE TO DEVELOP ALONG
A SURFACE DEW POINT BOUNDARY EXTENDING FROM SOUTHERN ARKANSAS TO
NORTHWESTERN TENNESSEE...AND WILL MOVE NORTHEAST, WHILE DEVELOPING
EASTWARD.

EXPECT WESTERN TENNESSEE TO REMAIN VULNERABLE INTO THE EARLY
NIGHTTIME HOURS FOR SEVERE THUNDERSTORMS, AND OTHER AREAS COULD
SEE SEVERE THUNDERSTORMS DEVELOP LATER IN THE NIGHT.

IT STILL LOOKS LIKE A SIGNIFICANT OUTBREAK OF SEVERE WEATHER
DEVELOPING FOR THE MID STATE ON WEDNESDAY, WITH TORNADOES, LARGE
HAIL, DAMAGING STRAIGHT LINE WINDS AND TORRENTIAL DOWNPOURS.

BELIEVE OUR SKIES WILL LIKELY BE CLOUDY OR MOSTLY CLOUDY WEDNESDAY
MORNING, BUT WILL BECOME PARTLY CLOUDY DURING THE AFTERNOON. THIS WILL
LEAD TO INCREASED POTENTIAL FOR RAPID DEVELOPMENT OF ROTATING SUPERCELLS
AND TORNADOES.

EVERYONE IN MIDDLE TENNESSEE IS ADVISED TO STAY TUNED TO A
RELIABLE SOURCE OF WEATHER INFORMATION THROUGH WEDNESDAY EVENING
AND LISTEN FOR ANY SEVERE THUNDERSTORM OR TORNADO WATCHES OR
WARNINGS THAT MIGHT BE ISSUED.

AFTER THE COLD FRONT PASSES WEDNESDAY EVENING, COOLER AND DRIER
AIR WILL SPREAD IN AND LOWS BY SUNRISE THURSDAY SHOULD BE IN THE
MIDDLE 40S TO LOWER 50S.

FRIDAY AND SATURDAY SHOULD BE DRY DAYS, WITH HIGHS IN THE 70S TO
LOWER 80S.

LONG TERM...ANOTHER COLD FRONT COMES IN EARLY NEXT WEEK BRINGING
ALONG ANOTHER INCREASED CHANCE OF SHOWERS AND THUNDERSTORMS.

HYDROLOGY...
HEAVY RAINFALL MOVING THROUGH MIDDLE TENNESSEE TOMORROW MAY CAUSE
AREA RIVERS TO REACH FLOOD STAGE. RIGHT NOW BASED ON 3-4 INCHES OF
RAIN...MINOR FLOODING IS POSSIBLE ON PORTIONS OF THE CUMBERLAND
RIVER BELOW CHEATHAM DAM...THE RED RIVER NEAR PORT ROYAL...THE
HARPETH RIVER BELOW BELLEVUE...THE DUCK RIVER BELOW
CENTERVILLE...THE BUFFALO RIVER NEAR LOBELVILLE...AND SHOAL CREEK
NEAR IRON CITY. MINOR FLOODING IS ALSO POSSIBLE ON THE TRIBUTARIES
OF THESE RIVERS...AS WELL AS LOCALIZED FLASH FLOODING. TWO WAVES
OF RAINFALL ARE EXPECTED...ONE OVERNIGHT AND ANOTHER WEDNESDAY
AFTERNOON EACH BRINGING 2 TO 3 INCHES OF RAIN. LOCALIZED RAINFALL
AMOUNTS IN EXCESS OF 6 INCHES ARE POSSIBLE...BUT WIDESPREAD
AMOUNTS OF 3 TO 6 INCHES ARE TO BE EXPECTED. THE FLOOD WATCH WILL
CONTINUE OVERNIGHT...AND UPGRADES TO FLOOD WARNINGS AND FLASH
FLOOD WARNINGS ARE POSSIBLE WEDNESDAY MORNING.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR TNZ005>011-022>034-
056>066-075-077>080-093>095.

WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR TNZ005>011-022>034-056>066-075-077>080-093>095.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
510 AM CDT TUE APR 26 2011

TNZ011-032>034-065-066-078>080-271000-
PICKETT-PUTNAM-OVERTON-FENTRESS-WHITE-CUMBERLAND-WARREN-GRUNDY-
VAN BUREN-
510 AM CDT TUE APR 26 2011

...FLASH FLOOD WATCH IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS ALL OF
MIDDLE TENNESSEE THROUGH TONIGHT. MAIN CONCERNS WITH SEVERE
THUNDERSTORMS THAT DEVELOP WILL BE ISOLATED TORNADOES...
DAMAGING WINDS...AND LARGE HAIL.

HEAVY RAINFALL IS EXPECTED ACROSS MIDDLE TENNESSEE THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A MAJOR SEVERE WEATHER OUTBREAK ACROSS MIDDLE TENNESSEE IS
EXPECTED ON WEDNESDAY. MAIN CONCERNS WITH SEVERE THUNDERSTORMS
THAT DEVELOP WILL BE TORNADOES...DAMAGING WINDS...AND LARGE HAIL.

HEAVY RAINFALL IS EXPECTED ACROSS MIDDLE TENNESSEE THROUGH WEDNESDAY
EVENING.

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

.SPOTTER INFORMATION STATEMENT...

REPORTS FROM TRAINED WEATHER SPOTTERS WILL LIKELY BE NEEDED.

TNZ005>010-022>031-056>064-075-077-093>095-271000-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-BENTON-HOUSTON-
HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-SMITH-
JACKSON-PERRY-HICKMAN-LEWIS-WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-
CANNON-DE KALB-BEDFORD-COFFEE-WAYNE-LAWRENCE-GILES-
510 AM CDT TUE APR 26 2011

...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS ALL OF
MIDDLE TENNESSEE THROUGH TONIGHT. MAIN CONCERNS WITH SEVERE
THUNDERSTORMS THAT DEVELOP WILL BE ISOLATED TORNADOES...
DAMAGING WINDS...AND LARGE HAIL.

HEAVY RAINFALL IS EXPECTED ACROSS MIDDLE TENNESSEE THROUGH WEDNESDAY
EVENING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A MAJOR SEVERE WEATHER OUTBREAK ACROSS MIDDLE TENNESSEE IS
EXPECTED ON WEDNESDAY. MAIN CONCERNS WITH SEVERE THUNDERSTORMS
THAT DEVELOP WILL BE TORNADOES...DAMAGING WINDS...AND LARGE HAIL.

HEAVY RAINFALL IS EXPECTED ACROSS MIDDLE TENNESSEE THROUGH WEDNESDAY
EVENING.

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

.SPOTTER INFORMATION 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

31

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
856 PM CDT TUE APR 26 2011

TNZ022-024-056-093-270245-
BENTON-HUMPHREYS-PERRY-WAYNE-
856 PM CDT TUE APR 26 2011

...SIGNIFICANT WEATHER ADVISORY FOR BENTON...HUMPHREYS...PERRY AND
WAYNE COUNTIES...

AT 844 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
SEVERE THUNDERSTORMS ALONG A LINE EXTENDING FROM 32 MILES WEST OF
BUENA VISTA TO 26 MILES WEST OF PINEFLAT...OR ALONG A LINE EXTENDING
FROM 43 MILES SOUTHWEST OF CAMDEN TO 31 MILES SOUTHWEST OF
SAVANNAH...MOVING EASTNORTHEAST AT 50 MPH.

THIS LINE OF STORMS HAS PRODUCED WIND DAMAGE AS IT PASSED THROUGH
WEST TENNESSEE DURING THE EVENING. ISOLATED TORNADOES ARE ALSO
LIKELY WITH THIS LINE OF STORMS AS IT MOVES EASTNORTHEAST.

RESIDENTS ALONG THE TENNESSEE RIVER FROM BENTON COUNTY SOUTH THROUGH
PERRY AND WAYNE NEED TO STAY ALERT FOR LATER STATEMENTS AND WARNINGS.

BOYD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
1054 PM CDT TUE APR 26 2011

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

1050 PM     TSTM WND DMG     LINDEN                  35.61N 87.84W
04/26/2011                   PERRY              TN   TRAINED SPOTTER

            TRAINED SPOTTER RPTS STRUCTURAL DAMAGE AND TREES DOWN IN
            LINDEN.

&&

TBOUCHER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
1059 PM CDT TUE APR 26 2011

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

1057 PM     HAIL             LINDEN                  35.61N 87.84W
04/26/2011  E1.00 INCH       PERRY              TN   TRAINED SPOTTER

            TRAINED SPOTTER RPTS HAIL OF ONE INCH DIAMETER.

&&

TBOUCHER

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
1257 AM CDT WED APR 27 2011

TNZ028-062-270630-
RUTHERFORD-WILSON-
1257 AM CDT WED APR 27 2011

...SIGNIFICANT WEATHER ADVISORY FOR RUTHERFORD AND WILSON COUNTIES...

AT 1257 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM 5 MILES NORTH OF WALTERHILL...OR 13 MILES NORTH
OF MURFREESBORO...MOVING NORTHEAST AT 40 MPH.

THIS STORM WILL BE NEAR...
  WATERTOWN

WINDS 40 TO 50 MPH ARE EXPECTED WITH THIS STORM.

31