MESOSCALE DISCUSSION 1633
   NWS STORM PREDICTION CENTER NORMAN OK
   0353 PM CDT SAT JUL 16 2011
   
   AREAS AFFECTED...PARTS OF N CNTRL SOUTH DAKOTA INTO CENTRAL NORTH
   DAKOTA
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 162053Z - 162230Z
   
   THE NEED FOR A WATCH APPEARS LIKELY AT SOME POINT LATE THIS
   AFTERNOON OR EVENING...PERHAPS WITHIN THE NEXT HOUR OR TWO.
   
   THE FOCUS AND FORCING FOR CONVECTIVE DEVELOPMENT LATE THIS AFTERNOON
   REMAIN A BIT UNCERTAIN.  THE CONVECTIVELY GENERATED OR ENHANCED
   BOUNDARY FROM THIS MORNING HAS BECOME LESS WELL DEFINED ...AND
   MID-LEVEL HEIGHTS ARE GENERALLY RISING.  HOWEVER...AN AXIS OF
   STRONGER SURFACE HEATING HAS OCCURRED SOUTHEAST OF THE BLACK HILLS
   INTO THE VICINITY OF BISMARCK...WHERE SURFACE DEW POINTS HAVE
   REACHED THE MID/UPPER 70S.  BENEATH STEEP LAPSE RATES...THIS HAS
   CONTRIBUTED TO LARGE CAPE IN EXCESS OF 4000 J/KG...WITH INHIBITION
   BECOMING INCREASINGLY NEGLIGIBLE.
   
   LOW-LEVEL WARM ADVECTION CURRENTLY APPEARS MAXIMIZED ACROSS SOUTH
   CENTRAL NORTH DAKOTA AND SEEMS TO OFFER THE HIGHEST CHANCES FOR
   STORM DEVELOPMENT...A BIT TO THE NORTH OF WHERE THE HIGH RESOLUTION
   RAPID REFRESH HAS SUGGESTED THE INITIATION OF STORMS DURING THE
   21-23Z TIME FRAME.  WHILE UNCERTAINTIES REMAIN... POTENTIAL FOR
   RAPID DEVELOPMENT AND INTENSIFICATION EXISTS IN THE PRESENCE OF
   SUFFICIENT SHEAR FOR SUPERCELLS.  ACTIVITY MAY BE ACCOMPANIED BY
   VERY LARGE HAIL AND THE RISK FOR AN ISOLATED TORNADO OR TWO.
   
   ..KERR.. 07/16/2011
   
   
   ATTN...WFO...ABR...BIS...
   
   LAT...LON   47030168 47670039 47179895 46289823 45409846 44359918
               44440078 45240118 45920180 47030168