

266 

WWUS20 KWNS 282311

SEL3

SPC WW 282311

OKZ000-TXZ000-290600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 633

NWS STORM PREDICTION CENTER NORMAN OK

610 PM CDT TUE JUL 28 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       THE OKLAHOMA PANHANDLE

       MUCH OF THE TEXAS PANHANDLE AND SOUTH PLAINS



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 610 PM

UNTIL 100 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 60

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTHEAST OF

GUYMON OKLAHOMA TO 25 MILES EAST SOUTHEAST OF LUBBOCK 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 631...WW 632...



DISCUSSION...THUNDERSTORMS ARE GRADUALLY INCREASING IN COVERAGE FROM

NE NM INTO THE W/NW TX AND OK PANHANDLES...AND NEW/ISOLATED

DEVELOPMENT IS OCCURRING FARTHER SE TOWARD THE AMA AND LBB AREAS.

DEEP LAYER BULK SHEAR AROUND 40 KT AND MLCAPE OF 1500-2000 J/KG ARE

FAVORABLE FOR SUPERCELLS.  STORMS SHOULD EVENTUALLY GROW UPSCALE

INTO AN MCS ACROSS THE TX PANHANDLE WITH AN ASSOCIATED WIND DAMAGE

THREAT BY LATE EVENING/TONIGHT...WHILE MORE DISCRETE SUPERCELLS

SHOULD PERSIST UNTIL LATE EVENING WITH AN ACCOMPANYING THREAT FOR

LARGE 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 32025.





...THOMPSON

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