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773 

WWUS20 KWNS 250258

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SPC WW 250258

LAZ000-TXZ000-250900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 710

NWS STORM PREDICTION CENTER NORMAN OK

1000 PM CDT SUN OCT 24 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN LOUISIANA

       NORTHEAST TEXAS



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 1000 PM UNTIL

400 AM CDT.



HAIL TO 2.5 INCHES 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 50

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 20 MILES EAST

SOUTHEAST OF MONROE LOUISIANA TO 35 MILES SOUTHWEST OF TYLER

TEXAS.  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.



OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES

TORNADO WATCH NUMBER 707. WATCH NUMBER 707 WILL NOT BE IN EFFECT

AFTER 1000 PM CDT. CONTINUE...WW 709...



DISCUSSION...THUNDERSTORMS WILL CONTINUE TO GENERATE NEAR AND E OF

AN OUTFLOW-DRYLINE INTERSECTION IN NE TX...AIDED BY A MIDLEVEL

SHORTWAVE TROUGH MOVING EWD OVER NE TX.  VERTICAL SHEAR AND

INSTABILITY WILL REMAIN SUFFICIENT FOR SUPERCELLS AND BOWING

SEGMENTS...WITH AN ATTENDANT RISK FOR LARGE HAIL AND DAMAGING WINDS.

 THOUGH AN ISOLATED TORNADO CANNOT BE RULED OUT...GRADUAL

STABILIZATION OF THE BOUNDARY LAYER SHOULD LIMIT THIS THREAT

OVERNIGHT.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 28025.





...THOMPSON

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