MESOSCALE DISCUSSION 1503
   NWS STORM PREDICTION CENTER NORMAN OK
   0609 PM CDT MON JUL 04 2011
   
   AREAS AFFECTED...PORTIONS ERN THROUGH S-CENTRAL ND...NRN MN
   INCLUDING ARROWHEAD AND LS NORTH SHORE.
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 596...
   
   VALID 042309Z - 050115Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 596
   CONTINUES.
   
   SVR TSTMS OVER NWRN MN MAY GROW UPSCALE INTO FORWARD-PROPAGATION MCS
   AND MOVE SEWD ACROSS REMAINDER NWRN/N-CENTRAL MN...WITH SOME
   BACKBUILDING STILL POSSIBLE INTO ERN ND.  ADDITIONALLY...MORE
   DISCRETE/WIDELY SCATTERED DEVELOPMENT OVER ERN ARROWHEAD AND
   ADJACENT PORTIONS ONT SHOULD MOVE SEWD WITH AT LEAST EPISODIC
   SUPERCELLULAR MODES POSSIBLE...AND ATTENDANT RISK OF LARGE HAIL AND
   SVR GUSTS.  ADDITIONAL WW MAY BE REQUIRED FOR NRN MN E OF WW 596. 
   EXISTING WW MAY BE CLEARED BEHIND COLD FRONT. 
   
   2230Z SFC MESOANALYSIS SHOWS COLD FRONT FROM SRN MB SWWD ACROSS
   NERN/S-CENTRAL ND...MOVING SEWD THROUGH DVL/BIS AREAS...AND FCST TO
   CONTINUE SEWD ACROSS REMAINDER ERN/SRN ND AND INTO NWRN MN THROUGH
   WW DURATION.  PREFRONTAL CONFLUENCE LINE...DRIFTING EWD...IS
   ANALYZED FROM RICHLAND COUNTY ND NNEWD OVER FAR...CKN AND MARSHALL
   COUNTY MN.  QUASISTATIONARY/MESOSCALE BAROCLINIC ZONE IS DRAWN FROM
   COOK COUNTY MN NWWD NEAR ONT STATIONS CWCH AND CYHD.  CAPPING SO FAR
   HAS HINDERED MAINTENANCE OF CONVECTIVE TOWERS ALONG COLD FRONT AND
   CONFLUENCE LINE.  THOUGH INITIATION CANNOT BE RULED OUT ALONG EITHER
   OF THOSE BOUNDARIES BEFORE OUTFLOW FROM MCS OVERTAKES THEM...THOSE
   INTERSECTIONS MAY SERVE AS LOCALIZED FOCI FOR ENHANCED LIFT DURING
   NEXT 2-3 HOURS.  PRIMARY CONCERN ATTM FOR ORGANIZED SVR THREAT IS
   POTENTIAL FOR EXPANSIVE COLD POOL WITH STG LEADING-EDGE ASCENT
   DEVELOPING FROM ACTIVITY NOW OVER NWRN MN...LEADING TO QLCS WITH
   WIND DAMAGE THREAT SPREADING SEWD OVER NRN MN.  MORE BACKED SFC
   WINDS E OF CONFLUENCE LINE WILL LEAD TO STRONGER STORM-RELATIVE
   INFLOW VERSUS FARTHER W.  PROSPECTIVE INFLOW-LAYER AIR MASS WILL BE
   FAVORABLE WITH SFC DEW POINTS 70S F CONTRIBUTING TO CORRIDOR OF
   MLCAPE 3000-4500 J/KG FROM JMS/ABR AREAS NEWD ACROSS NWRN MN.  CINH
   WILL INCREASE WITH SEWD EXTENT OVER NRN/CENTRAL MN GIVEN LOWER
   BOUNDARY LAYER THETAE...HOWEVER BY THAT TIME FORCED ASCENT MAY BE
   SUFFICIENT TO MAINTAIN MCS INTO THOSE AREAS.  SMALL-SCALE
   CONCENTRATION OF VORTICITY/LOW-LEVEL SHEAR ALONG ARROWHEAD/ONT
   BOUNDARY ALSO MAY SUPPORT SUPERCELL STRUCTURES...WITH WEAKLY CAPPED
   AIR MASS TO ITS SW...MLCAPE 1500-2000 J/KG AND EFFECTIVE SHEAR
   MAGNITUDES 35-45 KT.
   
   ..EDWARDS.. 07/04/2011
   
   
   ATTN...WFO...DLH...MPX...FGF...BIS...
   
   LAT...LON   47040028 48979736 48979508 49379510 49369495 49299479
               49089477 48959467 48769471 48699423 48659424 48609382
               48529380 48539348 48639342 48599286 48519262 48439276
               48449247 48199237 48359224 48379206 48219196 48169168
               48089165 48059137 48249084 48079076 48119009 47998991
               48038977 48008957 48068939 47908974 47649071 46779210
               46409364 46039616 45999929 47040028