MESOSCALE DISCUSSION 0950
   NWS STORM PREDICTION CENTER NORMAN OK
   1230 PM CDT FRI JUN 05 2009
   
   AREAS AFFECTED...NW NV...W CNTRL AND NW UT...INTO PARTS OF SRN ID
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 051730Z - 051930Z
   
   A SEVERE THREAT MAY INCREASE DURING THE 18-21Z TIME FRAME...MAINLY
   SOUTH/WEST OF THE SALT LAKE CITY AREA...ACROSS WEST CENTRAL/
   NORTHWEST UTAH.  THIS MAY BE FAIRLY LOCALIZED...AND A WATCH IS NOT
   CURRENTLY ANTICIPATED...BUT TRENDS WILL BE MONITORED.
   
   SCATTERED THUNDERSTORM DEVELOPMENT IS NOW WELL UNDERWAY... SUPPORTED
   BY FORCING FOR UPWARD VERTICAL MOTION IN THE EXIT REGION OF A
   MID/UPPER JET STREAK NOSING NORTHEASTWARD TO THE EAST OF THE CLOSED
   LOW CENTER NEAR THE CENTRAL CALIFORNIA COAST.  MID-LEVEL COOLING
   COUPLED WITH BOUNDARY LAYER HEATING IS CONTRIBUTING TO STEEPENING
   LAPSE RATES...WITH STRONGEST DESTABILIZATION LIKELY TO BECOME
   FOCUSED...BETWEEN NOW AND 21Z...NEAR A NARROW AXIS OF HIGHER
   MOISTURE CONTENT AIR PRESENT ACROSS THE GREAT SALT LAKE
   DESERT...PERHAPS INTO PARTS OF THE UPPER SNAKE VALLEY.  MIXED LAYER
   CAPE COULD EXCEED 1000 J/KG...AS 50-60 KT 500 MB FLOW OVERSPREADS
   WEST CENTRAL/NORTHWEST UTAH.  THIS WILL PROVIDE A FAVORABLE
   ENVIRONMENT FOR SUPERCELLS...CAPABLE OF PRODUCING AT LEAST LARGE
   HAIL.  DOWNWARD TRANSPORT OF MOMENTUM IN DOWNDRAFTS MAY SUPPORT
   DAMAGING WIND GUSTS...PARTICULARLY IN AREAS NOT SIGNIFICANTLY
   IMPACTED BY ONGOING CONVECTION.
   
   ..KERR.. 06/05/2009
   
   
   ATTN...WFO...SLC...PIH...BOI...LKN...
   
   LAT...LON   41551465 42571459 43221312 41781209 40351244 39481314
               39401395 40261451 41551465