MESOSCALE DISCUSSION 1853
   NWS STORM PREDICTION CENTER NORMAN OK
   0402 PM CDT SAT SEP 01 2012
   
   AREAS AFFECTED...MUCH OF UTAH...NERN NV...SRN ID...FAR SWRN WY
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 604...
   
   VALID 012102Z - 012230Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 604
   CONTINUES.
   
   SUMMARY...THE SEVERE THREAT CONTINUES FOR WW 604...WITH SOME THREAT
   EXTENDING OUTSIDE OF THE WATCH ACROSS PORTIONS OF NWRN NV INTO SRN
   ID. A DIMINISHING TREND FROM SOUTHWEST TO NORTHEAST IS EXPECTED WITH
   TIME.
   
   DISCUSSION...2030Z RADAR SHOWS NUMEROUS STRONG/POTENTIALLY SEVERE
   THUNDERSTORMS FROM PARTS OF NWRN NV INTO CNTRL AND NRN UT.
   CONVECTIVE MODE HAS LARGELY BEEN CELLULAR THUS FAR...WITH SEVERAL
   SUPERCELL STRUCTURES NOTED. THE CLUSTER OF STORMS MOVING INTO NWRN
   UT FROM NERN NV MAY CONGEAL INTO A LOOSELY ORGANIZED MCS IN THE NEXT
   1-2 HOURS...WITH AN INCREASING THREAT OF SEVERE WIND POTENTIALLY
   MOVING TOWARD THE SALT LAKE REGION BY 22-23Z. EVEN IF NO UPSCALE
   GROWTH OCCURS...SEVERE WIND/HAIL WILL REMAIN POSSIBLE WITH STRONGER
   CELLS...AS EFFECTIVE SHEAR OF 35-45 KTS REMAINS SUFFICIENT FOR
   ORGANIZED STORM MODES. SOME SEVERE THREAT WILL EXTEND INTO SRN
   ID...AS STORMS DEVELOP OR MOVE INTO THE REGION. 
   
   THE STORMS SOUTH OF SALT LAKE MOVING FROM CNTRL INTO NERN UT HAVE
   SHOWN SOME WEAKENING AND MAY CONTINUE TO SLOWLY DIMINISH AS THEY
   MOVE INTO A SOMEWHAT LESS UNSTABLE ENVIRONMENT. AT THIS TIME...IT
   DOES NOT APPEAR THAT A DOWNSTREAM WATCH WILL NE NECESSARY...BUT SOME
   THREAT OF ISOLATED SEVERE WIND OR HAIL WILL PERSIST EAST OF THE
   WATCH. 
   
   A GENERAL WEAKENING TREND FROM SW TO NE IS LIKELY LATER THIS
   AFTERNOON AS DRIER AIR MOVES INTO THE REGION.
   
   ..DEAN.. 09/01/2012
   
   
   ATTN...WFO...RIW...GJT...SLC...PIH...VEF...BOI...LKN...
   
   LAT...LON   39811569 41281624 42181564 42551460 42501258 42471131
               42161046 41610986 41240973 40660968 39900974 39110985
               38530996 38241075 38201180 38131332 38281425 38941487
               39811569