MESOSCALE DISCUSSION 1730
   NWS STORM PREDICTION CENTER NORMAN OK
   0552 PM CDT THU SEP 18 2014

   AREAS AFFECTED...S-CNTRL MT

   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

   VALID 182252Z - 182345Z

   PROBABILITY OF WATCH ISSUANCE...20 PERCENT

   SUMMARY...AN ISOLATED SEVERE WIND GUST AND LARGE HAIL THREAT WILL
   PROBABLY CONTINUE FOR THE NEXT FEW HOURS.

   DISCUSSION...RADAR MOSAIC SHOWS SEVERAL VIGOROUS STORMS OVER S-CNTRL
   MT IN STILLWATER COUNTY.  SURFACE OBSERVATIONS TO THE EAST AND
   DOWNSTREAM OVER THE EWD-MOVING STORMS HAVE WARMED INTO THE 70S WITH
   DEWPOINTS IN THE 50S.  MODIFYING AREA RAP SOUNDINGS FOR CURRENT
   SURFACE CONDITIONS YIELDS AROUND 500-1000 J/KG MLCAPE.  STRONG
   UNIDIRECTIONAL WLY FLOW INCREASING WITH HEIGHT /KBLX VAD/ HAS LED TO
   AROUND 40 KT EFFECTIVE BULK SHEAR --SUPPORTIVE OF ORGANIZED STORM
   STRUCTURES.  THE GRADUAL EWD PROGRESSION OF THE LARGE-SCALE W COAST
   TROUGH AND ASSOCIATED ASCENT WILL ACT TO PARTIALLY DELAY THE
   DETRIMENTAL EFFECTS OF COOLING THIS EVENING.  EVENTUAL NOCTURNAL
   STABILIZATION VIA THE LOSS OF DAYTIME HEATING SHOULD ACT TO LIMIT
   POTENTIAL FOR SEVERE STRAIGHT-LINE WIND GUSTS AND LARGE HAIL.

   ..SMITH/GOSS.. 09/18/2014


   ATTN...WFO...BYZ...

   LAT...LON   45700969 46290723 46080656 45720639 45120679 45030992
               45320997 45700969