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327 

WWUS20 KWNS 141717

SEL1

SPC WW 141717

UTZ000-150000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 741

NWS STORM PREDICTION CENTER NORMAN OK

1120 AM MDT MON SEP 14 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       MUCH OF UTAH



EFFECTIVE THIS MONDAY MORNING AND EVENING FROM 1120 AM UNTIL 600

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 80

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

NORTHWEST OF OGDEN UTAH TO 30 MILES EAST SOUTHEAST OF BRYCE

CANYON UTAH.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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.



DISCUSSION...STRONG/SEVERE THUNDERSTORMS DEVELOPING WRN UT AHEAD OF

UPPER TROUGH.  WITH HEATING/STEEPENING LAPSE RATES AND MLCAPES

CLIMBING TO NEAR 1000 J/KG...STORMS WILL CONTINUE INCREASING IN

COVERAGE/INTENSITY THRU THE AFTERNOON AS THEY DEVELOP NEWD.

CLUSTERS AND SHORT LINE SEGMENTS WILL INCREASE THREAT OF DAMAGING

WINDS ALONG WITH THE LARGE HAIL CONCERN WITH ANY STRONG UPDRAFT.



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 450. MEAN STORM

MOTION VECTOR 22030.





...HALES

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