

240 

WWUS20 KWNS 310409

SEL3

SPC WW 310409

TXZ000-310900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 643

NWS STORM PREDICTION CENTER NORMAN OK

1110 PM CDT THU JUL 30 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       MUCH OF SOUTHWEST TEXAS



EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 1110 PM

UNTIL 400 AM 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 80

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST

NORTHEAST OF HOBBS NEW MEXICO TO 70 MILES SOUTH OF MARFA TEXAS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 641...



DISCUSSION...WELL DEVELOP CLUSTER OF SEVERE THUNDERSTORMS AND

ASSOCIATED COLD POOL HAS MOVED INTO SERN NM.  WITH A MDTLY UNSTABLE

AND FAVORABLY SHEARED ENVIRONMENT ACROSS THE WATCH AREA...STORMS

WILL CONTINUE TO BE A THREAT OF DAMAGING WINDS AND LARGE HAIL FOR

SEVERAL MORE HOURS.



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 33025.





...HALES

