

363 

WWUS20 KWNS 182159

SEL0

SPC WW 182159

COZ000-KSZ000-NEZ000-OKZ000-TXZ000-190500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 710

NWS STORM PREDICTION CENTER NORMAN OK

500 PM CDT TUE AUG 18 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN COLORADO

       WESTERN KANSAS

       SOUTHWEST NEBRASKA

       OKLAHOMA PANHANDLE

       TEXAS PANHANDLE



EFFECTIVE THIS TUESDAY AFTERNOON FROM 500 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 70

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES WEST

NORTHWEST OF MCCOOK NEBRASKA TO 35 MILES SOUTH SOUTHWEST OF

AMARILLO TEXAS.  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.



OTHER WATCH INFORMATION...CONTINUE...WW 709...



DISCUSSION...SEVERAL CLUSTERS OF INTENSE THUNDERSTORMS OVER EASTERN

CO AND NORTHEAST NM WILL TRACK EASTWARD THIS AFTERNOON AND EVENING

INTO THE WATCH AREA.  A COMBINATION OF MODERATE

INSTABILITY...SUFFICIENT VERTICAL SHEAR...AND LARGE SCALE FORCING

ASSOCIATED WITH AN APPROACHING TROUGH WILL MAINTAIN A RISK OF LARGE

HAIL AND DAMAGING WINDS THROUGH MOST OF THE EVENING.



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 500. MEAN STORM

MOTION VECTOR 27025.





...HART

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