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464 

WWUS20 KWNS 160049

SEL6

SPC WW 160049

ALZ000-FLZ000-MSZ000-CWZ000-160800-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 146

NWS STORM PREDICTION CENTER NORMAN OK

745 PM CDT FRI APR 15 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHERN ALABAMA

       THE WESTERN FLORIDA PANHANDLE

       EXTREME SOUTHEAST MISSISSIPPI

       COASTAL WATERS



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 745 PM

UNTIL 300 AM CDT.



TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 90 STATUTE

MILES EAST AND WEST OF A LINE FROM 30 MILES NORTHWEST OF LA

GRANGE GEORGIA TO 20 MILES EAST OF MOBILE ALABAMA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU6).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS.



OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO

WATCH NUMBER 141. WATCH NUMBER 141 WILL NOT BE IN EFFECT AFTER

745 PM CDT. CONTINUE...WW 142...WW 143...WW 144...WW 145...



DISCUSSION...CLUSTERS OF SUPERCELLS IN CENTRAL/SRN AL AND SE MS WILL

CONTINUE TO SPREAD EWD THROUGH THE OVERNIGHT HOURS IN ADVANCE OF THE

MS VALLEY MIDLEVEL TROUGH AND SURFACE BOUNDARY.  WEAK-MODERATE

INSTABILITY AND STRONG VERTICAL SHEAR WILL BE MAINTAINED OVER THIS

AREA...AND THE TORNADO/SEVERE THREAT WILL EXPAND EWD TONIGHT AS THE

LOW LEVELS MOISTEN FARTHER E INTO SE AL AND THE FL PANHANDLE.  A

STRONG TORNADO OR TWO WILL REMAIN POSSIBLE FOR THE NEXT SEVERAL

HOURS...GIVEN THE PRESENCE OF DISCRETE SUPERCELLS IN A MOIST

ENVIRONMENT WITH EFFECTIVE SRH NEAR 500 M2/S2.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

550. MEAN STORM MOTION VECTOR 27030.





...THOMPSON

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