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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 50

NWS STORM PREDICTION CENTER NORMAN OK

125 PM CDT MON MAR 14 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND NORTHERN ALABAMA

       EASTERN LOUISIANA

       CENTRAL AND SOUTHERN MISSISSIPPI



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 125 PM UNTIL 900

PM CDT.



HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTH

SOUTHEAST OF MC COMB MISSISSIPPI TO 55 MILES NORTH NORTHWEST OF

BIRMINGHAM ALABAMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



DISCUSSION...PRE-FRONTAL BAND OF TSTMS WILL CONTINUE TO INTENSIFY

THIS AFTERNOON IN ADVANCE OF COMPACT MID/UPPER-LEVEL LOW ADVANCING

THROUGH THE OZARK PLATEAU.  RELATIVELY COOL MIDLEVEL TEMPERATURES

COUPLED WITH A WARMING/MOISTENING BOUNDARY WILL SUPPORT CORRIDORS OF

MODEST DESTABILIZATION INTO THIS EVENING WITH MLCAPE VALUES

APPROACHING 500-1500 J/KG.  THIS DESTABILIZATION IN CONJUNCTION WITH

A GRADUALLY STRENGTHENING WIND FIELD AND RESULTANT 35-45 KT OF DEEP

SWLY SHEAR WILL BE SUPPORTIVE OF EMBEDDED BOWING STRUCTURES.



REGION FROM E-CNTRL MS INTO NRN AL WILL CONTINUE TO EXHIBIT

VERTICALLY-VEERING WIND PROFILES/LARGER LOW-LEVEL HODOGRAPHS INTO

THIS EVENING...AND AS SUCH SOME POTENTIAL FOR A BRIEF TORNADO OR TWO

WILL EXIST.  HOWEVER...GIVEN THE EVOLVING LINEAR CONVECTIVE

MODE...DAMAGING WIND GUSTS APPEAR TO BE THE PRIMARY THREAT.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION

VECTOR 26035.





...MEAD

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