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000 

WWUS20 KWNS 032050

SEL0

SPC WW 032050

WYZ000-040400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 220

NWS STORM PREDICTION CENTER NORMAN OK

250 PM MDT THU MAY 3 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN WYOMING



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

1000 PM 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 50

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES WEST

SOUTHWEST OF CHEYENNE WYOMING TO 45 MILES NORTH NORTHWEST OF

GILLETTE WYOMING.  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 217...WW 218...WW 219...



DISCUSSION...STORMS CONTINUE TO DEVELOP ALONG MID LEVEL TROUGH

MOVING NNEWD THRU THE REGION.  AIR MASS IS POTENTIALLY UNSTABLE WITH

MUCAPE OF 1000 J/KG MAINLY FROM NERN NATRONA COUNTY INTO ERN JOHNSON

COUNTY NWD.  THREAT OF DAMAGING WIND AND HAIL EXISTS WITH THIS

ACTIVITY.



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 19035.





...MCCARTHY

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