MESOSCALE DISCUSSION 1668
   NWS STORM PREDICTION CENTER NORMAN OK
   1043 AM CDT WED JUL 20 2011
   
   AREAS AFFECTED...NERN ND THROUGH NWRN MN
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 666...
   
   VALID 201543Z - 201645Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 666
   CONTINUES.
   
   SOME THREAT FOR ISOLATED DAMAGING WIND AND POSSIBLY HAIL WILL
   PERSIST NEXT HOUR MAINLY OVER NWRN MN...BUT OVERALL THREAT APPEARS
   INCREASINGLY MARGINAL.
   
   LATE THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM N-CNTRL
   MN SWWD THROUGH CNTRL ND WHERE IT INTERSECTS A COLD FRONT THAT
   STRETCHES SWWD INTO WY. THE PRIMARY ZONE OF MORE ROBUST STORM
   DEVELOPMENT HAS BEEN NORTH OF THE OUTFLOW BOUNDARY WITHIN ZONE OF
   ISENTROPIC LIFT ACROSS NWRN MN. HOWEVER...THIS ZONE OF ASCENT HAS
   BEEN GRADUALLY SHIFTING NWD. FARTHER SW...AN MCV IS MOVING NEWD
   THROUGH SERN ND...AND A FEW ELEVATED STORMS HAVE DEVELOPED WITHIN
   ZONE OF MID LEVEL ASCENT ATTENDING THIS FEATURE. THE MOIST AND
   UNSTABLE WARM SECTOR BOUNDARY LAYER WILL PROBABLY REMAINED CAPPED TO
   SURFACE BASED STORMS NEXT SEVERAL HOURS. SO AS THE CONVECTION IN
   NERN MN SHIFTS INTO ONTARIO...IT IS UNLIKELY THAT ACTIVITY IN SERN
   ND WILL BECOME ROOTED IN THE BOUNDARY LAYER GIVEN STRENGTH OF CAP
   AND SHALLOW NATURE OF LIFT ALONG THE SWD ADVANCING OUTFLOW BOUNDARY.
   
   ..DIAL.. 07/20/2011
   
   
   ATTN...WFO...FGF...
   
   LAT...LON   48809496 48499445 47629455 47399610 47589760 48689762
               48939654 48809496