

580 

WWUS20 KWNS 241054

SEL7

SPC WW 241054

ARZ000-LAZ000-MSZ000-TXZ000-CWZ000-241900-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 807

NWS STORM PREDICTION CENTER NORMAN OK

450 AM CST THU DEC 24 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SMALL PART OF SOUTH-CENTRAL AND SOUTHEASTERN ARKANSAS

       LOUISIANA EXCEPT FAR NORTHWEST AND FAR SOUTHEAST PORTIONS

       PORTIONS OF WESTERN MISSISSIPPI

       PORTIONS OF EAST TEXAS

       COASTAL WATERS



EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 450 AM UNTIL

100 PM CST.



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

TO 75 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH NORTHEAST OF

MONROE LOUISIANA TO 55 MILES SOUTH SOUTHWEST OF INTRACOASTAL CITY

LOUISIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 806. WATCH NUMBER 806 WILL NOT BE IN EFFECT AFTER

450 AM CST.



DISCUSSION...BANDS OF STG-SVR TSTMS WILL CONTINUE TO MOVE EWD ACROSS

WW AREA...WITH POTENTIAL FOR DAMAGING GUSTS AND A FEW TORNADOES FROM

BOTH EMBEDDED SUPERCELLS AND BOW/LEWP FORMATIONS.  PRECEDING THIS

ACTIVITY...RELATIVELY DISCRETE CELLS MAY ROTATE AND POSE TORNADO

THREAT IN ENVIRONMENT OF FAVORABLE AMBIENT VERTICAL SHEAR AND AT

LAST MARGINAL BUOYANCY S OF SURFACE WARM FRONT.



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

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.

MEAN STORM MOTION VECTOR 22035.





...EDWARDS/THOMPSON

