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000 

WWUS20 KWNS 301356

SEL0

SPC WW 301356

TXZ000-301900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 310

NWS STORM PREDICTION CENTER NORMAN OK

855 AM CDT WED MAY 30 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND EASTERN TEXAS



EFFECTIVE THIS WEDNESDAY MORNING AND AFTERNOON FROM 855 AM UNTIL

200 PM CDT.



HAIL TO 2 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 90

STATUTE MILES EITHER SIDE OF A LINE FROM 30 MILES NORTHEAST OF

DALLAS TEXAS TO 40 MILES SOUTH SOUTHEAST OF HUNTSVILLE 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...CONTINUE...WW 309...



DISCUSSION...BOW ECHO/DERECHO CONTINUES TO MOVE SEWD AT 40 KT.  AIR

MASS CONTINUES TO BE FAVORABLY MOIST AND UNSTABLE FOR CONVECTION TO

CONTINUE SEWD FOR THE NEXT SEVERAL HOURS.  MLCAPE VALUES ARE

1500-1800 J/KG AND ANALYSIS ALSO INDICATES DEEP LAYER SHEAR OF 30-35

KT.  MORNING RAOB ANALYSIS INDICATES REAR INFLOW JET OVER CENTRAL OK

OF 50-60 KT...THUS THREAT CONTINUES TO DAMAGING WINDS AND HAIL.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 31035.





...MCCARTHY

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