MESOSCALE DISCUSSION 1483
   NWS STORM PREDICTION CENTER NORMAN OK
   0144 PM CDT TUE JUL 17 2012
   
   AREAS AFFECTED...SERN MT...WRN ND/SD
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 171844Z - 171945Z
   
   PROBABILITY OF WATCH ISSUANCE...40 PERCENT
   
   SUMMARY...ALTHOUGH A FEW ELEVATED THUNDERSTORMS ARE OCCURRING OVER
   THE BLACK HILLS...THE AREA IS BEING MONITORED FOR ADDITIONAL...MORE
   ORGANIZED DEVELOPMENT.
   
   DISCUSSION...AN ERN GREAT BASIN VORTICITY MAX HAS REACHED N CNTRL WY
   /PER 1830Z WV IMAGERY/. THE IMPLIED FORCING FOR ASCENT IN
   COMBINATION WITH A WEAK LEE SURFACE TROUGH EXTENDING FROM SERN MT
   INTO NERN WY AND THE HIGHER TERRAIN OF THE BLACK HILLS MAY PROVIDE
   SEVERAL MUDDLED AREAS OF INCREASED VERTICAL DEVELOPMENT. HI-RES
   CONSENSUS GENERALLY SUPPORTS CONVECTIVE DEVELOPMENT ACROSS THESE
   AREAS WITHIN THE NEXT FEW HOURS...POSSIBLY EVOLVING INTO A LOOSELY
   ORGANIZED CLUSTER ACROSS THE DAKOTAS GIVEN SUFFICIENT LOW-LEVEL
   MOISTURE /SURFACE DEW POINTS IN THE LOWER 60S F/ AND 8 C/KM
   MID-LEVEL LAPSE RATES PER 12Z RAP SOUNDING. HOWEVER...WEAK AND
   DISORGANIZED SHEAR PROFILES MAY LIMIT OVERALL ORGANIZATION...WITH
   COVERAGE OF EXPECTED SEVERE STORMS UNCERTAIN AT THIS TIME.
   
   ..HURLBUT/MEAD.. 07/17/2012
   
   
   ATTN...WFO...BIS...UNR...BYZ...
   
   LAT...LON   43860478 44310541 45500535 46410510 46280394 45940350
               44800316 44010338 43660431 43860478