MESOSCALE DISCUSSION 1696
   NWS STORM PREDICTION CENTER NORMAN OK
   0546 PM CDT FRI JUL 22 2011
   
   AREAS AFFECTED...NE SD...SE ND AND WRN MN
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 222246Z - 230015Z
   
   A SEVERE THREAT IS LIKELY TO DEVELOP ACROSS NERN SD...SE ND AND WRN
   MN EARLY THIS EVENING. AN ISOLATED TORNADO THREAT ALONG WITH A
   POTENTIAL FOR LARGE HAIL AND WIND DAMAGE WILL LIKELY EXIST ACROSS
   THE MCD AREA. WW ISSUANCE WILL BE POSSIBLE ACROSS THE REGION.
   
   ISOLATED THUNDERSTORMS ARE INITIATING IN NERN SD ALONG THE NRN EDGE
   OF AN AXIS OF STRONG INSTABILITY WHERE MESOANALYSIS INDICATES MLCAPE
   VALUES ARE IN THE 2500 TO 3500 J/KG RANGE. THE STORMS ARE INITIATING
   ALONG A WELL-DEFINED FRONTAL BOUNDARY WHERE LOW-LEVEL CONVERGENCE IS
   ENHANCED. THE ABERDEEN WSR-88D VWP SHOWS ABOUT 40 KT OF DEEP LAYER
   SHEAR SUGGESTING SUPERCELL DEVELOPMENT WILL BE POSSIBLE WITH THE
   ONGOING CONVECTION. A THREAT FOR LARGE HAIL WILL LIKELY EXIST
   ESPECIALLY FROM ABERDEEN WWD WHERE SOME SHORT-TERM MODEL FORECASTS
   INITIATE NEW CELLS ALONG THE FRONTAL BOUNDARY EARLY THIS EVENING AND
   MID-LEVEL LAPSE RATES ARE STEEPER THAN AREAS TO THE EAST. AN
   ISOLATED TORNADO THREAT MAY ALSO DEVELOP AS LOW-LEVEL FLOW INCREASES
   EARLY THIS EVENING. IN ADDITION...THE STORMS ARE LOCATED IN A VERY
   MOIST ENVIRONMENT WITH MID 70S F DEWPOINTS LOCATED ACROSS NERN SD
   WHICH MAY AID A POTENTIAL FOR WET DOWN BURSTS.
   
   ..BROYLES.. 07/22/2011
   
   
   ATTN...WFO...MPX...FGF...FSD...ABR...BIS...
   
   LAT...LON   45520049 45120049 44769988 44529795 44709675 45129602
               45869560 46899653 46969852 46749949 46409996 46050020
               45520049