MESOSCALE DISCUSSION 1690
   NWS STORM PREDICTION CENTER NORMAN OK
   0300 PM CDT FRI JUL 22 2011
   
   AREAS AFFECTED...ERN SD...IA AND CENTRAL/SRN MN
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 222000Z - 222130Z
   
   MONITORING PORTIONS OF ERN SD...CENTRAL/WRN IA...AND CENTRAL/SRN MN
   FOR A POSSIBLE WATCH.
   
   CONVECTIVE EVOLUTION IN THE MIDDLE MO RIVER VALLEY IS SOMEWHAT
   UNCERTAIN...THOUGH MOST OPERATIONAL AND HIGH RESOLUTION MODELS
   SUGGEST CONVECTION WILL DEVELOP IN THIS AREA SOON. IF SURFACE BASED
   STORMS DEVELOP...MODERATE TO STRONG INSTABILITY AND 30-40 KT WLY
   DEEP LAYER SHEAR WOULD SUPPORT A SEVERE STORM THREAT. LATEST VSBY
   SATELLITE IMAGERY SHOWS A MCV  MOVING EWD ACROSS WEST CENTRAL
   MN...WHILE ANOTHER WAS MOVING ENEWD INTO NWRN IA. THE BEST FORCING
   APPEARED TO BE LOCATED AHEAD OF THE IOWA MCV...WHERE
   EXTENSIVE CLOUDS AND SOME PCPN HAVE PERSISTED AHEAD OF THIS FEATURE.
   HOWEVER...TEMPERATURES HAVE WARMED INTO THE 80S UNDER THESE
   CLOUDS...WITH LOWER 90S PREVALENT SOUTH OF THE THICKER CLOUD BAND. A
   FEW ELEVATED STORMS HAD RECENTLY DEVELOPED IN NRN IA...AND ALSO IN
   FAR ERN SD NEAR WEAKENING FRONTAL BOUNDARY. AREA IS BEING MONITORED
   FOR ORGANIZED DEVELOPMENT OF STORMS...AND IF THAT HAPPENS..A WW
   WOULD BECOME MORE LIKELY.
   
   ..IMY.. 07/22/2011
   
   
   ATTN...WFO...DVN...ARX...MPX...DMX...FSD...OAX...ABR...
   
   LAT...LON   41339262 40969365 40609458 40749563 43279693 44349875
               45519852 45339550 45099314 43799225 42029230 41339262