

010 

WWUS20 KWNS 312217

SEL6

SPC WW 312217

COZ000-KSZ000-NMZ000-OKZ000-TXZ000-010500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 646

NWS STORM PREDICTION CENTER NORMAN OK

520 PM CDT FRI JUL 31 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF SOUTHEAST COLORADO

       PARTS OF WESTERN KANSAS

       PARTS OF NORTHEAST NEW MEXICO

       MUCH OF OKLAHOMA PANHANDLE

       PARTS OF TEXAS PANHANDLE



EFFECTIVE THIS FRIDAY AFTERNOON FROM 520 PM UNTIL MIDNIGHT 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 80 MILES NORTH

NORTHWEST OF GARDEN CITY KANSAS TO 20 MILES SOUTH SOUTHEAST OF

TUCUMCARI NEW MEXICO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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 644...WW 645...



DISCUSSION...THUNDERSTORMS ARE INCREASING IN NUMBER AND INTENSITY

OVER HIGH PLAINS AHEAD OF A WEAK UPPER TROUGH.  STEEP LAPSE RATES

AND 30-35 KT OF SHEAR SUPPORT GENERATION OF COLD POOLS AND

ASSOCIATED DAMAGING WIND THREAT AS STORMS MOVE/DEVELOP E/SE ACROSS

WATCH



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 28030.





...HALES

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