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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 332

NWS STORM PREDICTION CENTER NORMAN OK

250 PM MDT FRI JUN 5 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHEAST COLORADO

       EXTREME NORTHWEST KANSAS

       WESTERN NEBRASKA

       SOUTHEAST WYOMING



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

1000 PM MDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE

MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF TORRINGTON

WYOMING TO 55 MILES SOUTH SOUTHEAST OF AKRON COLORADO.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU2).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



DISCUSSION...DESPITE WIDESPREAD HIGH CLOUDS...A FEW THUNDERSTORMS

HAVE DEVELOPED RECENTLY OVER THE LARAMIE RANGE IN SE WY.  CONTINUED

UPSLOPE FLOW OF BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 50S AND SLOW

SURFACE HEATING WILL CONTRIBUTE TO INCREASING CAPE...WEAKENING

CONVECTIVE INHIBITION...AND ADDITIONAL THUNDERSTORM DEVELOPMENT FROM

WY INTO CO.  GIVEN THE MODERATE INSTABILITY /MLCAPE NEAR 2000 J/KG

AND MID LEVEL LAPSE RATES NEAR 8 C/KM/ AND EFFECTIVE BULK SHEAR OF

45-55 KT...ENVIRONMENT WILL SUPPORT SUPERCELLS CAPABLE OF PRODUCING

ISOLATED VERY LARGE HAIL AND DAMAGING WINDS.  LOW-LEVEL SHEAR

INCREASES WITH EWD EXTENT AND WITH TIME THIS EVENING AS THE LLJ

STRENGTHENS...AND THIS INCREASING SHEAR WILL LIKEWISE SUPPORT AN

INCREASING THREAT FOR A FEW TORNADIC SUPERCELLS THIS EVENING.



AVIATION...TORNADOES AND 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.





...THOMPSON

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