MESOSCALE DISCUSSION 1793
   NWS STORM PREDICTION CENTER NORMAN OK
   0547 AM CDT SAT JUL 30 2011
   
   AREAS AFFECTED...SE ND...NE SD AND SW MN
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 301047Z - 301215Z
   
   A SEVERE THREAT WILL CONTINUE TO DEVELOP SEWD ACROSS NE SD AND MAY
   REACH SW MN LATER THIS MORNING. AN ISOLATED THREAT FOR HAIL AND WIND
   DAMAGE MAY EXIST WITH THE MORE INTENSE CELLS OVER THE NEXT FEW
   HOURS. WW CAN NOT BE RULED OUT ACROSS THE REGION THIS MORNING.
   
   A LARGE THUNDERSTORM IS ONGOING IN SE ND ON THE NERN EDGE OF A
   POCKET OF MODERATE INSTABILITY WHERE MLCAPE VALUES RANGE FROM 1500
   TO 2000 J/KG. THE STORM IS BEING SUPPORTED BY A BAND OF LARGE-SCALE
   ASCENT ASSOCIATED WITH A NRN PLAINS SHORTWAVE TROUGH AND BY A 35 TO
   45 KT LOW-LEVEL JET EXTENDING NEWD INTO SE ND. THE LOW-LEVEL JET
   ALONG WITH WLY FLOW IN THE MID-LEVELS OF ABOUT 40 KT EVIDENT ON THE
   ABERDEEN WSR-88D VWP IS CREATING MODERATE DEEP LAYER SHEAR
   SUFFICIENT FOR A SEVERE THREAT. ALTHOUGH THE ACTIVITY IS ELEVATED
   ATTM...THE STORMS MAY BECOME MORE CLOSELY SFC-BASED MOVING SEWD INTO
   A VERY MOIST AIRMASS ACROSS NE SD AND SW MN WHERE SFC DEWPOINTS ARE
   IN THE LOWER 70S F. THE VERY MOIST AIRMASS COMBINED WITH 35-40 KT OF
   LOW-LEVEL FLOW SHOULD BE SUFFICIENT FOR A WIND DAMAGE THREAT
   ESPECIALLY IF A MORE EXTENSIVE LINE SEGMENT CAN ORGANIZE. IN
   ADDITION...MESOANALYSIS CURRENTLY SHOWS A DISTINCT PLUME OF STEEP
   MID-LEVEL LAPSE RATES EXTENDING EWD ACROSS MUCH OF SD INTO SW MN.
   THIS ALONG WITH 40 KT OF DEEP LAYER SHEAR SHOULD SUPPORT AN ISOLATED
   HAIL THREAT AS WELL.
   
   ..BROYLES.. 07/30/2011
   
   
   ATTN...WFO...MPX...FGF...FSD...ABR...BIS...
   
   LAT...LON   45149450 46599731 46879850 46779912 46509941 46189957
               45919945 45179843 44689715 44099560 44229459 44509422
               45149450