

941 

WWUS20 KWNS 131957

SEL7

SPC WW 131957

COZ000-NEZ000-WYZ000-140300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 397

NWS STORM PREDICTION CENTER NORMAN OK

155 PM MDT SAT JUN 13 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       A LARGE PORTION OF EASTERN COLORADO

       MUCH OF NEBRASKA PANHANDLE

       PARTS OF EASTERN WYOMING



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 155 PM UNTIL

900 PM MDT.



TORNADOES...HAIL TO 2 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 50 MILES NORTH OF DOUGLAS

WYOMING TO 50 MILES SOUTH OF LIMON COLORADO.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU7).



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...WITH APPROACH OF S/WV TROUGH FROM UT/WRN CO...SHEAR

PROFILES AND INSTABILITY ARE BECOMING FAVORABLE FOR DEVELOPMENT OF

SEVERE THUNDERSTORMS...PRIMARILY EAST OF MOUNTAINS.  WITH MLCAPES

AOA 1200 J/KG AND 40KT OF SHEAR...SUPERCELLS ARE ILKLEY WITH

POTENTIAL FOR LARGE HAIL AND TORNADOES.  ACTIVITY WILL GRADUALLY

DEVELOP EWD ACROSS THE WATCH INTO THE MORE FAVORABLE LOW LEVEL

SHEAR/INSTABILITY ENVIRONMENT.



AVIATION...TORNADOES AND 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

500. MEAN STORM MOTION VECTOR 24025.





...HALES

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