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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 9

NWS STORM PREDICTION CENTER NORMAN OK

840 AM CST TUE FEB 1 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       MUCH OF LOUISIANA

       WEST CENTRAL AND SOUTHWEST MISSISSIPPI

       COASTAL WATERS



EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 840 AM UNTIL

300 PM CST.



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

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



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 100 STATUTE

MILES EAST AND WEST OF A LINE FROM 60 MILES NORTH OF NATCHEZ

MISSISSIPPI TO 45 MILES SOUTH OF INTRACOASTAL CITY LOUISIANA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU9).



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.



DISCUSSION...A STRONGLY FORCED SQUALL LINE MOVE QUICKLY EWD IN

CONJUNCTION WITH A SURFACE COLD FRONT PROGRESSING EWD FROM TX INTO

LA...AND STRONG MIDLEVEL TROUGH EJECTING ENEWD OVER TX/OK.  GRADUAL

SURFACE MOISTENING/DESTABILIZATION WILL SUPPORT CONVECTION BASED

NEAR THE SURFACE AS DEWPOINTS INCREASE INTO THE 60S...WHILE VERTICAL

SHEAR WILL BE VERY STRONG AND SUPPORTIVE OF EMBEDDED BOW/SUPERCELL

STRUCTURES IN THE LINE.  A FEW TORNADOES AND DAMAGING WINDS WILL BE

THE MAIN THREATS INTO THE AFTERNOON.



AVIATION...TORNADOES AND 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 24045.





...THOMPSON

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