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WWUS20 KWNS 111518

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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 278

NWS STORM PREDICTION CENTER NORMAN OK

1020 AM CDT WED MAY 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND NORTH CENTRAL TEXAS



EFFECTIVE THIS WEDNESDAY MORNING AND EVENING FROM 1020 AM UNTIL

600 PM 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 60

STATUTE MILES EAST AND WEST OF A LINE FROM 10 MILES WEST

NORTHWEST OF SHERMAN TEXAS TO 45 MILES SOUTHWEST OF JUNCTION

TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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...CONTINUE...WW 277...



DISCUSSION...STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE

OF PRE-FRONTAL CONVERGENCE THROUGH CNTRL AND NCNTRL TX WHERE THE

ATMOSPHERE IS MODERATELY UNSTABLE WITH STEEP LAPSE RATES. VERTICAL

SHEAR FROM 35-45 KT WILL SUPPORT ORGANIZED STORM STRUCTURES WITH

DAMAGING WIND AND LARGE HAIL THE MAIN THREATS.



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 24035.





...DIAL

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