MESOSCALE DISCUSSION 1593
   NWS STORM PREDICTION CENTER NORMAN OK
   0156 PM CDT TUE JUL 12 2011
   
   AREAS AFFECTED...WRN/CNTRL MT
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 121856Z - 122000Z
   
   STRONG TO SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL WILL
   DEVELOP EARLY THIS AFTERNOON...WITH A THREAT OF DMGG WIND BECOMING
   POSSIBLE LATER TODAY. AREA IS BEING MONITORED FOR A POSSIBLE WW.
   
   HIGH-BASED CUMULUS CONTINUES TO INCREASE ACROSS CNTRL ID/WRN MT IN
   ADVANCE OF IMPLIED FORCING FOR ASCENT OBSERVED ON 1830Z WV IMAGERY
   FROM NWRN MT SWWD TO NRN CA/NWRN NV. ALTHOUGH THE TRUE COLD FRONT
   REMAINS TO THE WEST THROUGH ERN WA...CNTRL ORE...AND NWRN CA...A
   SUBTLE WIND SHIFT AND A SHARP GRADIENT IN THE CU FIELD SEEM TO
   DEMARCATE A SUBTLE SURFACE BOUNDARY FROM SWRN MT SWWD TO NEAR BOISE.
   AN ADDITIONAL TERRAIN-INDUCED STATIONARY FRONT EXISTS TO THE LEE OF
   THE ROCKIES. THE CU FIELD WILL LIKELY CONTINUE TO INCREASE ALONG THE
   SUBTLE SURFACE FEATURE...AND IN RESPONSE TO WEAK LOW LEVEL UPSLOPE
   FLOW FARTHER E. MODIFIED AREA 12Z SOUNDINGS INDICATE CURRENT
   CONVECTION IS LIKELY STILL ELEVATED. AS SUCH...AN INITIAL THREAT OF
   HAIL WILL BE PROBABLE...WITH DMGG WINDS BECOMING INCREASINGLY
   POSSIBLE THIS AFTERNOON AS DESTABILIZATION CONTINUES AND STORMS
   BECOME MORE SURFACE-BASED WITH TIME. 30-40 KTS EFFECTIVE SHEAR WILL
   BE CONDUCIVE TO ORGANIZED CELLS AND CLUSTERS.
   
   ..HURLBUT.. 07/12/2011
   
   
   ATTN...WFO...BYZ...TFX...MSO...
   
   LAT...LON   48971363 48961157 47211050 46420998 45790984 45251051
               45071187 45071321 46051419 48941470 48971363