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WWUS20 KWNS 061951

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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 445

NWS STORM PREDICTION CENTER NORMAN OK

250 PM CDT TUE JUL 6 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF NORTHEAST COLORADO

       LARGE PART OF WESTERN AND NORTHERN NEBRASKA

       PARTS OF SOUTHEAST WYOMING



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 250 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 75

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 20 MILES NORTHWEST

OF CHEYENNE WYOMING TO 20 MILES NORTH OF ONEILL NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU5).



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 444...



DISCUSSION...THUNDERSTORMS ARE DEVELOPING ALONG FRONTAL BOUNDARY

THAT EXTENDS FROM CHERRY COUNTY TO CYS.  IN ADDITION STORMS WILL

DEVELOP EWD OFF THE HIGHER TERRAIN OF NERN CO/SERN WY.  WITH MLCAPES

AOA 1000 J/KG...STEEP LAPSE RATES AND 30-35 KT OF SHEAR...SEVERE

STORMS ARE LIKELY...INCLUDING LARGE HAIL AND DAMAGING DOWNBURST

WINDS.  ISOLATED SUPERCELLS ARE ALSO POSSIBLE INCREASING BOTH HAIL

AND WIND THREAT AS WELL AS POSSIBLE BRIEF TORNADO'S/LAND SPOUTS.



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 550. MEAN STORM

MOTION VECTOR 27020.





...HALES

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