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146 

WWUS20 KWNS 082048

SEL2

SPC WW 082048

OKZ000-TXZ000-090400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 352

NWS STORM PREDICTION CENTER NORMAN OK

350 PM CDT MON JUN 8 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EXTREME SOUTHWEST OKLAHOMA

       NORTHWEST TEXAS



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 350 PM UNTIL

1100 PM CDT.



HAIL TO 3 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 70

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES NORTH OF

BIG SPRING TEXAS TO 40 MILES SOUTHEAST OF WICHITA FALLS TEXAS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 350...WW 351...



DISCUSSION...RAPID THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG A

PRE-FRONTAL TROUGH ACROSS NW TX FROM 21-22Z...AND ADDITIONAL STORMS

COULD FORM LATER THIS EVENING ALONG THE SYNOPTIC COLD FRONT FARTHER

NE INTO SW OK.  STRONG INSTABILITY AND A WEAKENING CAP ACROSS NW TX

THROUGH DAYTIME HEATING/MIXING...AND THE APPROACH OF A SUBTLE

MID-UPPER LEVEL SPEED MAX FROM SE NM...WILL SUPPORT AT LEAST

SCATTERED SEVERE STORMS THROUGH EARLY TONIGHT.  MLCAPE IN EXCESS OF

3000 J/KG AND EFFECTIVE BULK SHEAR OF AT LEAST 40 KT WILL FAVOR

SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WINDS.

RELATIVELY LARGE TEMPERATURE-DEW POINT SPREADS AND STORM

MERGERS/UPSCALE GROWTH LATER THIS EVENING WILL ALSO SUPPORT AN

INCREASING THREAT OF DAMAGING WINDS.  ANY TORNADO THREAT WILL LIKELY

BE LIMITED BY THE RELATIVELY HIGH LCL HEIGHTS AND SOMEWHAT MODEST

LOW-LEVEL SHEAR.



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

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 27020.





...THOMPSON

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