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697 

WWUS20 KWNS 011906

SEL4

SPC WW 011906

UTZ000-WYZ000-020300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 604

NWS STORM PREDICTION CENTER NORMAN OK

100 PM MDT SAT SEP 1 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND NORTHERN UTAH

       SOUTHWEST WYOMING



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 100 PM UNTIL

900 PM MDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH

NORTHWEST OF EVANSTON WYOMING TO 25 MILES EAST OF MILFORD UTAH.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU4).



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 602...WW 603...



DISCUSSION...TSTMS EXPECTED TO INCREASE OVER FAR ERN NV AND

CNTRL/NRN UT WITH CONTINUED SFC HEATING AHEAD OF ERN NV UPR IMPULSE.

SYSTEM IS EMBEDDED IN SEASONABLY STRONG...UNIDIRECTIONAL SWLY

MID/UPR-LVL FLOW /WITH 700-500 MB SPEEDS OF 35-40 KTS/. AMPLE

MOISTURE/SHEAR APPEAR PRESENT FOR SUSTAINED STORMS...INCLUDING

SUPERCELLS/BOWING SEGMENTS WITH DMGG WIND AND HAIL. STORMS MAY

EVOLVE INTO A LOOSELY-ORGANIZED CLUSTER GIVEN PRESENCE OF SW-NE

OUTFLOW BOUNDARIES OVER CNTRL/NRN UT LEFT BY EARLIER STORMS. A

TORNADO CANNOT BE RULED OUT...ESPECIALLY NEAR THESE BOUNDARIES.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 23035.





...CORFIDI

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