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852 

WWUS20 KWNS 022212

SEL9

SPC WW 022212

KSZ000-OKZ000-TXZ000-030500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 649

NWS STORM PREDICTION CENTER NORMAN OK

515 PM CDT SUN AUG 2 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF WESTERN KANSAS

       MUCH OF OKLAHOMA PANHANDLE

       PARTS OF NORTHERN TEXAS PANHANDLE



EFFECTIVE THIS SUNDAY AFTERNOON FROM 515 PM UNTIL MIDNIGHT CDT.



HAIL TO 2.5 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTHEAST OF

HILL CITY KANSAS TO 40 MILES SOUTH SOUTHEAST OF GUYMON OKLAHOMA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 648...



DISCUSSION...STREAM OF MOIST AND VERY UNSTABLE AIR MASS RESIDES

ACROSS THE WATCH AREA.  WITH STEEP LAPSE RATES AND 30-35 KT OF

SHEAR...SEVERE THUNDERSTORMS INCLUDING ISOLATED SUPERCELLS ARE

EXPECTED TO DEVELOP EWD ACROSS THE WATCH.  PRIMARY THREAT WILL BE

VERY LARGE HAIL AND DAMAGING DOWNBURSTS...PARTICULARLY ASSOCIATED

WITH SUPERCELLS.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 33020.





...HALES

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