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000 

WWUS20 KWNS 212225

SEL0

SPC WW 212225

COZ000-KSZ000-NEZ000-220600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 920

NWS STORM PREDICTION CENTER NORMAN OK

425 PM MDT TUE OCT 21 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN COLORADO

       WESTERN KANSAS

       SOUTHWEST NEBRASKA



EFFECTIVE THIS TUESDAY AFTERNOON FROM 425 PM UNTIL MIDNIGHT MDT.



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 40 MILES WEST

NORTHWEST OF MCCOOK NEBRASKA TO 60 MILES SOUTH SOUTHEAST OF LAMAR

COLORADO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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...POWERFUL COLD FRONT WILL SURGE SOUTHEASTWARD THIS

EVENING ACROSS EASTERN CO AND WESTERN KS.  DESPITE ONLY MARGINAL

INSTABILITY...STRONG FORCING ALONG FRONT WILL LIKELY RESULT IN

SCATTERED THUNDERSTORMS.  STEEP LAPSE RATES AND INCREASING LOW/MID

LEVEL WIND FIELDS INDICATE A RISK OF HAIL AND DAMAGING WINDS IN

STRONGER CELLS THROUGH THE EVENING.



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 400. MEAN STORM

MOTION VECTOR 27030.





...HART

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