347  
ACUS11 KWNS 042012  
SWOMCD  
SPC MCD 042012  
MNZ000-IAZ000-SDZ000-042145-  
 
MESOSCALE DISCUSSION 0980  
NWS STORM PREDICTION CENTER NORMAN OK  
0312 PM CDT THU JUN 04 2026  
 
AREAS AFFECTED...EASTERN SOUTH DAKOTA INTO SOUTHWESTERN MINNESOTA  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 042012Z - 042145Z  
 
PROBABILITY OF WATCH ISSUANCE...60 PERCENT  
 
SUMMARY...THUNDERSTORM COVERAGE IS EXPECTED TO INCREASE ACROSS  
EASTERN SOUTH DAKOTA AND SOUTHWESTERN MINNESOTA THIS  
AFTERNOON/EVENING, WITH POTENTIAL FOR LARGE HAIL AND STRONG TO  
SEVERE WIND GUSTS.  
 
DISCUSSION...THUNDERSTORM COVERAGE HAS INCREASED OVER THE PAST HOUR  
ACROSS PORTIONS OF EASTERN SOUTH DAKOTA ALONG/AHEAD OF A SLOW MOVING  
SURFACE COLD FRONT CURRENTLY EXTENDING SOUTHWESTWARD FROM NEAR THE  
ND/SD/MN BORDER TO SOUTH-CENTRAL SOUTH DAKOTA. AHEAD OF THIS  
BOUNDARY, LATEST OBJECTIVE ANALYSIS INDICATES LINGERING INHIBITION  
IS ERODING, WITH WARMING TEMPERATURES CONTRIBUTING TO MLCAPE OF  
1500-2000 J/KG. WHILE A MARGINAL INCREASE IN MID-LEVEL FLOW IS  
EXPECTED THROUGH THE EVENING, EFFECTIVE SHEAR WILL REMAIN WEAKER  
THAN AREAS FARTHER WEST (GENERALLY REMAINING LESS THAN 30-35 KTS).  
THIS IS LIKELY TO SUPPORT AN INITIALLY DISCRETE STORM MODE (WITH  
MARGINAL SUPERCELL STRUCTURES POSSIBLE) WITH A GRADUAL TRANSITION TO  
A MORE OUTFLOW-DOMINANT, MULTICELLULAR STORM MODE.  
 
WHILE MID-LEVEL LAPSE RATES ARE NOT AS STEEP COMPARED TO AREAS  
FARTHER WEST (EVIDENT VIA A COMPARISON OF THE 18Z UNR AND ABR  
OBSERVED SOUNDINGS), LARGE HAIL WILL BE POSSIBLE WITH INITIALLY  
DISCRETE CONVECTION AND MORE ROBUST UPDRAFTS. STEEP LOW-LEVEL LAPSE  
RATES WILL ALSO PROMOTE A RISK FOR STRONG TO SEVERE WIND GUSTS. A  
BRIEF TORNADO/LANDSPOUT ALSO CANNOT BE RULED OUT SHOULD A STRONGER  
LOW-LEVEL UPDRAFT INTERACT WITH MARGINALLY ENHANCED SURFACE VERTICAL  
VORTICITY/LOW-LEVEL SHEAR IN CLOSE PROXIMITY TO THE SURFACE FRONT.  
TRENDS ARE BEING MONITORED FOR POSSIBLE SEVERE THUNDERSTORM WATCH  
ISSUANCE.  
 
..CHALMERS/MOSIER.. 06/04/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...MPX...FGF...FSD...ABR...  
 
LAT...LON 43289941 44029936 44139934 44389861 44659813 45099763  
45509739 45699705 45799668 45879633 45879600 45789562  
45639553 45419544 44919541 44349567 43849607 43349652  
43089737 43049813 43029869 43079917 43289941  
 
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH  
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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