788  
ACUS11 KWNS 210308  
SWOMCD  
SPC MCD 210308  
MNZ000-NDZ000-210445-  
 
MESOSCALE DISCUSSION 1390  
NWS STORM PREDICTION CENTER NORMAN OK  
1008 PM CDT FRI JUN 20 2025  
 
AREAS AFFECTED...SOUTHEAST NORTH DAKOTA  
 
CONCERNING...TORNADO WATCH 448...  
 
VALID 210308Z - 210445Z  
 
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 448 CONTINUES.  
 
SUMMARY...A PAIR OF LONG-LIVED SUPERCELLS WILL RESIDE WITHIN A  
FAVORABLE TORNADO ENVIRONMENT FOR AT LEAST THE NEXT 1-2 HOURS BEFORE  
MERGING WITH AN APPROACHING MCS.  
 
DISCUSSION...OVER THE PAST TWO HOURS, A PAIR OF LONG-LIVED  
SUPERCELLS (ONE OF WHICH HAS A HISTORY OF PRODUCING 2-3 INCH HAIL  
AND MULTIPLE TORNADOES) HAVE MEANDERED SLOWLY EAST/SOUTHEASTWARD  
ALONG THE I-94 CORRIDOR AND ARE MOVING TOWARDS A REGIONAL BUOYANCY  
MAXIMUM (MLCAPE ESTIMATED TO BE AROUND 4000 J/KG) DRIVEN BY RICH  
LOW-LEVEL MOISTURE (DEWPOINTS IN THE LOW 70S). THIS RICH MOISTURE  
WILL HELP MODULATE THE INFLUENCE OF NOCTURNAL LOW-LEVEL  
STABILIZATION AND HELP MAINTAIN VERY BUOYANT NEAR-SURFACE PARCELS.  
ADDITIONALLY, THE APPROACH OF A MID-LEVEL PERTURBATION FROM THE WEST  
IS INDUCING A LOW-LEVEL MASS RESPONSE THAT IS RESULTING IN A  
STRENGTHENING OF THE LOW-LEVEL JET - AND CONSEQUENTLY INCREASING  
LOW-LEVEL SRH - AS SAMPLED BY RECENT KABR VWP OBSERVATIONS. THESE  
TRENDS SUGGEST THAT THE DOWNSTREAM ENVIRONMENT MAY BECOME  
INCREASINGLY SUPPORTIVE OF TORNADIC SUPERCELLS IN THE SHORT TERM.  
GIVEN THIS ENVIRONMENT AND VELOCITY IMAGERY FROM KMVX, IT IS  
ESTIMATED THAT STRONG (EF-2 TO EF-3) TORNADOES WILL REMAIN POSSIBLE.  
WITH TIME, THESE SUPERCELLS WILL EVENTUALLY MERGE WITH THE  
APPROACHING MCS FROM THE WEST. BASED ON RECENT STORM TRACKS, THIS  
APPEARS MOST PROBABLE DURING THE 04-05 UTC TIME FRAME, AT WHICH  
POINT THE PRIMARY THREAT WILL BECOME WIDESPREAD SEVERE WINDS.  
 
..MOORE.. 06/21/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...FGF...BIS...  
 
LAT...LON 46269797 46399824 46629828 47089808 47249737 47259699  
47159681 46799671 46579670 46429676 46239687 46159699  
46099718 46269797  
 
MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH  
MOST PROBABLE PEAK WIND GUST...75-90 MPH  
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN  
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