MESOSCALE DISCUSSION 1998
   NWS STORM PREDICTION CENTER NORMAN OK
   0144 AM CDT TUE SEP 08 2009
   
   AREAS AFFECTED...WESTERN/CENTRAL ND AND NORTHERN SD
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 080644Z - 080815Z
   
   SEVERE HAIL WILL REMAIN POSSIBLE THROUGH THE OVERNIGHT ACROSS
   PORTIONS OF WESTERN/CENTRAL ND AND ADJACENT NORTHERN SD. A WATCH IS
   NOT CURRENTLY ANTICIPATED...BUT CONVECTIVE TRENDS WILL CONTINUE TO
   BE MONITORED.
   
   TIED TO A LEAD MID LEVEL IMPULSE...MULTIPLE ONGOING ELEVATED
   SUPERCELLS /WITH HISTORY OF LARGE HAIL/ WILL LIKELY CONTINUE TO
   DEVELOP ENE ALONG/JUST BEHIND AN EASTWARD ADVANCING SURFACE FRONT
   ACROSS THE DAKOTAS. ATOP A COOL/STABLE SURFACE LAYER...MODERATE
   INSTABILITY/STEEP LAPSE RATE ENVIRONMENT WILL SUPPORT AMPLE BUOYANCY
   FOR LARGE HAIL MAINLY OVER THE NEXT FEW HOURS...WITH AS MUCH AS
   40-50 KT OF EFFECTIVE BULK SHEAR ON THE COOL SIDE OF THE FRONT
   CONDUCIVE FOR UPDRAFT ROTATION/ENHANCED HAIL POTENTIAL. THE NEED FOR
   A WATCH IS UNCLEAR GIVEN THE RELATIVELY ISOLATED NATURE OF THE
   SEVERE RISK AND/OR POTENTIAL EVOLUTION OF MORE WIDESPREAD BUT LESS
   INTENSE STORMS.
   
   ..GUYER.. 09/08/2009
   
   
   ATTN...WFO...ABR...BIS...UNR...
   
   LAT...LON   48190221 48860104 48400027 45640103 46160349 48190221