Severe Thunderstorm Warning 47, NWS Huntsville, AL

403 
WWUS54 KHUN 041822
SVSHUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
122 PM CDT MON APR 4 2011

ALC033-077-041831-
/O.EXP.KHUN.SV.W.0047.000000T0000Z-110404T1830Z/
LAUDERDALE AL-COLBERT AL-
122 PM CDT MON APR 4 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN COLBERT AND
NORTHWESTERN LAUDERDALE COUNTIES EXPIRES AT 130 PM CDT...

WEATHER SERVICE DOPPLER RADAR INDICATES THE THUNDERSTORM THAT 
PROMPTED THE INITIAL WARNING HAS WEAKENED AND IS NO LONGER SEVERE. 
THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN ALLOWED TO EXPIRE.

HOWEVER...A LINE OF STRONG TO SEVERE THUNDERSTORMS WAS RAPIDLY 
APPROACHING NORTHWEST ALABAMA AND ADDITIONAL WARNINGS WILL LIKELY BE 
ISSUED SHORTLY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 600 PM CDT MONDAY EVENING FOR
NORTHERN ALABAMA AND CENTRAL TENNESSEE.

LAT...LON 3501 8778 3476 8811 3478 8812 3489 8810
      3494 8815 3497 8817 3500 8820 3502 8819
TIME...MOT...LOC 1821Z 238DEG 56KT 3494 8803

$$

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1203 PM CDT MON APR 4 2011

.UPDATE...FOR 18Z TAFS.

&&

.AVIATION...
MAIN AVIATION FOCUS IN THE SHORT TERM /NEXT 6 HOURS/ WILL BE
DEVELOPMENT OF STRONG TO SEVERE THUNDERSTORMS AHEAD OF A LINE OF
SEVERE THUNDERSTORMS CURRENTLY MOVING ACROSS THE MS RIVER. AS THIS
TIME...EXPECT TSTMS TO DEVELOP BETWEEN 19-21Z ACROSS NW/NC AL AHEAD
OF MAIN LINE. THESE STORMS WILL LIKELY PRODUCE WIND GUSTS > 40KTS IN
ADDITION TO VERY HEAVY RAIN. LOW VSBY/CIGS IN +RA COULD CREATE BRIEF
IFR CONDITIONS. MAIN LINE OF TSTMS ASSOCIATED WITH STRONG COLD FRONT
WILL MOVE WEST-TO-EAST ACROSS THE AREA BETWEEN 22Z-02Z. ADDITIONAL
HEAVY RAIN AND STRONG WINDS CAN BE EXPECTED. WINDS WILL SHIFT TO THE
NORTHWEST BEHIND TO THE FRONT WITH GUSTS 20-25KTS THROUGH AT LEAST
03Z. SEVERE THREAT/HEAVY RAIN WILL DIMINISH BEHIND THE COLD FRONTAL
PASSAGE EARLY THIS EVENING. DJN.83

&&

.DISCUSSION...
A LINE OF STORMS IS STARTING TO CONGEAL IN THE MISS RIVER VALLEY TO
OUR WEST. SOME OF THIS ACTIVITY HAS RAPIDLY DEVELOPED IN THE LAST
HOUR...AND WILL CONTINUE TO DEVELOP AND STRENGTHEN AS THE LINE PUSHES
INTO AN AREA OF GREATER INSTABILITY. LATEST SFC ANALYSIS INDICATES
MOSTLY MID/UPR 60S DEW POINTS IN SOUTHERN MISS...WITH A SMALL POOLING
OF 70 DEW POINTS NEAR THE MISS RIVER CHANNEL. THIS MOIST AXIS WILL BE
PUSHED EASTWARD AHEAD OF THE APPROACHING TROUGH AND SQUALL LINE AS
THE MORNING AND EARLY AFTERNOON PROGRESSES.

MEANWHILE...AHEAD OF THE MAIN LINE...A POSSIBLE GRAVITY WAVE FEATURE
HAS INITIATED CONVECTION IN PORTIONS OF NORTHERN MISS AND WRN TENN.
SOME OF THESE CELLS HAVE INTENSE CORES AND MAY HAVE PRODUCED NEAR
QUARTER SIZE HAIL ALREADY. ALTHOUGH CLOUD COVER IS PROVIDING A
LIMITING FACTOR TO DESTABILIZATION...FURTHER WARM/MOIST ADVECTION
FROM THE SW SHOULD HELP TO OVERCOME THE CAPPING INVERSION EARLY THIS
AFTERNOON. THUS...EXPECTING TO SEE MORE THUNDERSTORM ACTIVITY
DEVELOPING AHEAD OF THE MAIN SQUALL LINE. 30-35KT BULK SHEAR ACROSS
OUR AREA WILL BE FAVORABLE FOR SUPERCELLS AND A CONTINUED LARGE HAIL
AND TORNADO/DAMAGING WIND THREAT WITH THESE CELLS.

TIMING WITH THE SQUALL LINE REMAINS MUCH THE SAME AS FORECAST
PREVIOUSLY AND IS AS FOLLOWS...
LAUDERDALE/COLBERT/FRANKLIN/LAWRENCE.......1-3 PM CDT
LIMESTONE/MADISON/MORGAN/CULLMAN/LINCOLN...3-5 PM CDT
MARSHALL/DEKALB/JACKSON/MOORE/FRANKLIN.....5-7 PM CDT

THIS IS THE BEST TIMING ATTM...GIVE OR TAKE ABOUT AN HOUR. WITH THE
SQUALL LINE...LOOKS LIKE A DAMAGING WIND THREAT WITH TOP WINDS
AROUND 60-80 MPH. ADDITIONALLY...HAIL PERHAPS UP TO GOLF BALL SIZE
AND ISOLATED TORNADOES IN EMBEDDED BOWING AND BROKEN LINE SEGMENTS
WILL BE POSSIBLE.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: COLBERT...CULLMAN...DEKALB...FRANKLIN AL...JACKSON...
LAUDERDALE...LAWRENCE...LIMESTONE...MADISON...MARSHALL...MORGAN.

TN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: FRANKLIN TN...LINCOLN...MOORE.

&&

AVIATION...DJN
DISCUSSION...KDW

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1230 PM CDT MON APR 4 2011

ALZ001>010-016-TNZ076-096-097-050200-
LAUDERDALE-COLBERT-FRANKLIN AL-LAWRENCE-LIMESTONE-MADISON-MORGAN-
MARSHALL-JACKSON-DEKALB-CULLMAN-MOORE-LINCOLN-FRANKLIN TN-
1230 PM CDT MON APR 4 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH ALABAMA AND PORTIONS
OF SOUTHERN MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT...

A SQUALL LINE...WITH STRONG TO SEVERE STORMS...WILL AFFECT NORTHWEST
ALABAMA BETWEEN 1 PM AND 3 PM...THE HUNTSVILLE AREA BETWEEN 3 PM AND
5 PM AND NORTHEAST ALABAMA BETWEEN 5 PM AND 7 PM. A FEW DISCRETE
THUNDERSTORM CELLS WILL ALSO BE POSSIBLE AHEAD OF THE SQUALL LINE.

THE MAIN SEVERE WEATHER THREAT WILL BE DAMAGING WINDS. HOWEVER LARGE
HAIL...LOCALLY HEAVY RAINFALL AND ISOLATED TORNADOES WILL ALSO BE
POSSIBLE.

THE SEVERE WEATHER THREAT WILL DIMINISH ACROSS THE AREA FROM WEST TO
EAST DURING THE EVENING AS THE SQUALL LINE MOVES OUT OF THE
TENNESSEE VALLEY.

IN ADDITION...WINDS OUTSIDE ANY THUNDERSTORM ACTIVITY WILL BE
SUSTAINED AROUND 20 TO 25 MPH...WITH GUSTS UP TO 40 MPH. A WIND
ADVISORY WILL REMAIN IN EFFECT THROUGH 7 PM THIS EVENING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

A FEW THUNDERSTORMS ARE POSSIBLE ON FRIDAY AND FRIDAY NIGHT.

.SPOTTER CALL TO ACTION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL...IN
SUPPORT OF SEVERE WEATHER OPERATIONS IS REQUESTED THIS AFTERNOON
INTO THE EARLY EVENING.

SS/KDW

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1254 PM CDT MON APR 4 2011

ALZ001>003-041830-
COLBERT-FRANKLIN-LAUDERDALE-
1254 PM CDT MON APR 4 2011

...SIGNIFICANT WEATHER ADVISORY FOR COLBERT...FRANKLIN AND LAUDERDALE
COUNTIES UNTIL 130 PM CDT...

AT 1251 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
SEVERE THUNDERSTORMS ALONG A LINE EXTENDING FROM 20 MILES WEST OF
CORINTH TO 40 MILES WEST OF TUPELO...MOVING EAST AT 60 MPH. THESE
THUNDERSTORMS HAVE HAD A HISTORY OF PRODUCING DAMAGING WIND GUSTS IN
SOUTHERN PORTIONS OF WEST TENNESSEE.

PEOPLE IN WESTERN COLBERT...FRANKLIN AND LAUDERDALE
COUNTIES...SHOULD MONITOR THE WEATHER SITUATION CLOSELY. LISTEN FOR
POSSIBLE WARNINGS AND BE PREPARED TO TAKE APPROPRIATE ACTION SHOULD
SEVERE WEATHER THREATEN.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO...OR YOUR LOCAL
TELEVISION STATIONS FOR LATER STATEMENTS AND POSSIBLE WARNINGS
CONCERNING THIS WEATHER SITUATION.

&&

LAT...LON 3499 8777 3432 8816 3489 8810 3492 8814
      3501 8820
TIME...MOT...LOC 1751Z 273DEG 52KT 3497 8882 3423 8938

KDW