MESOSCALE DISCUSSION 1613
   NWS STORM PREDICTION CENTER NORMAN OK
   1204 PM CDT THU JUL 14 2011
   
   AREAS AFFECTED...CNTRL MT
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 141704Z - 141900Z
   
   A WATCH LIKELY WILL BE NEEDED AT SOME POINT THIS AFTERNOON.  CURRENT
   INDICATIONS ARE THIS MAY BE CLOSER TO 20Z...BUT AN ISOLATED SEVERE
   THREAT MAY DEVELOP EARLIER.
   
   LOW-LEVEL LAPSE RATES ARE BEGINNING TO STEEPEN WITH INSOLATION...
   AND AT LEAST POCKETS OF MODERATE BOUNDARY LAYER CAPE UP TO AROUND
   1000+ J/KG APPEAR POSSIBLE WITHIN THE NEXT COUPLE OF HOURS... BEFORE
   BECOMING MORE WIDESPREAD TOWARD THE 20-22Z TIME FRAME.  AS A
   RESULT...RECENT INTENSIFYING TRENDS TO A STORM WEST/NORTHWEST OF
   LEWISTOWN PROBABLY WILL CONTINUE.  ON THE EDGE OF A BELT OF 40-50+
   KT SOUTHWESTERLY 500 MB FLOW...VERTICAL SHEAR IS ALREADY SUFFICIENT
   FOR SUPERCELLS...AND THE RISK FOR SEVERE HAIL/WIND COULD INCREASE
   ACROSS PARTS OF NORTH CENTRAL MONTANA AS EARLY AS 18-19Z.  A MORE
   SUBSTANTIVE OR WIDESPREAD SEVERE WEATHER THREAT... THOUGH...IS STILL
   NOT EXPECTED UNTIL LATER THIS AFTERNOON...AIDED BY BETTER FORCING
   ASSOCIATED WITH UPSTREAM CLOSED LOW/UPPER TROUGH GRADUALLY LIFTING
   INTO ALBERTA/SASKATCHEWAN.
   
   ..KERR.. 07/14/2011
   
   
   ATTN...WFO...BYZ...GGW...TFX...
   
   LAT...LON   47071084 48171015 48960963 48900758 48640684 47200724
               45390891 45170987 45881107 47071084