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379 

WWUS20 KWNS 221957

SEL3

SPC WW 221957

COZ000-KSZ000-NEZ000-230300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 613

NWS STORM PREDICTION CENTER NORMAN OK

255 PM CDT WED JUL 22 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHEAST COLORADO

       NORTHWEST KANSAS

       SOUTHWEST AND SOUTH-CENTRAL NEBRASKA



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 255 PM UNTIL

1000 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 70

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 35 MILES SOUTHWEST

OF AKRON COLORADO TO 45 MILES SOUTH SOUTHEAST OF KEARNEY

NEBRASKA.  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.



DISCUSSION...TSTMS ARE DEVELOPING ALONG W-E ORIENTED BOUNDARY IN

CONJUNCTION WITH PASSAGE OF SHORT WAVE TROUGH THROUGH WRN/CNTRL NEB

INTO KS.  PRESENCE OF STEEP LOW TO MIDLEVEL LAPSE RATES...MLCAPE OF

1000-2000 J/KG AND 35-45 KT OF DEEP NWLY SHEAR WILL LIKELY PROMOTE

ORGANIZED STORM CLUSTERS /INCLUDING SUPERCELLS/ WITH THE THREAT FOR

LARGE HAIL AND DAMAGING WIND GUSTS.



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 35030.





...MEAD/HALES

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