184  
ACUS11 KWNS 201337  
SWOMCD  
SPC MCD 201337  
MIZ000-WIZ000-201530-  
 
MESOSCALE DISCUSSION 1671  
NWS STORM PREDICTION CENTER NORMAN OK  
0837 AM CDT MON JUL 20 2026  
 
AREAS AFFECTED...WESTERN UPPER PENINSULA OF MICHIGAN AND ADJACENT  
WISCONSIN  
 
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY  
 
VALID 201337Z - 201530Z  
 
PROBABILITY OF WATCH ISSUANCE...20 PERCENT  
 
SUMMARY...ISOLATED DAMAGING WINDS AND MARGINALLY SEVERE HAIL ARE  
POSSIBLE THIS MORNING. A GRADUAL WEAKENING TREND IS ANTICIPATED AND  
A WATCH IS NOT EXPECTED. TRENDS WILL CONTINUE TO BE MONITORED.  
 
DISCUSSION...A SMALL ELEVATED LINEAR SEGMENT HAS MOVED INTO THE  
WESTERN UPPER PENINSULA OF MICHIGAN. THE OBSERVED SOUNDINGS FROM INL  
AND APX THIS MORNING SHOW AROUND 7 C/KM MID-LEVEL LAPSE RATES. THIS  
ACTIVITY IS CURRENTLY BEING DRIVEN BY MODERATE LOW-LEVEL WARM  
ADVECTION. WITH TIME, HOWEVER, THE LOW-LEVEL JET WILL WEAKEN AND  
VEER. ELEVATED BUOYANCY WILL BE ABLE TO SUSTAIN ROBUST CONVECTION  
FOR ANOTHER HOUR OR TWO AS IT MOVES SOUTHEASTWARD AT AROUND 35 KT.  
THE OVERALL EXPECTATION IS FOR THIS LINEAR SEGMENT TO OUTPACE  
FAVORABLE BUOYANCY BEFORE LOW-LEVEL MOISTENING INCREASES LATER  
TODAY. ISOLATED DAMAGING WINDS WILL BE THE MAIN THREAT THIS MORNING,  
THOUGH STEEP MID-LEVEL LAPSE RATES COULD SUPPORT MARGINALLY SEVERE  
HAIL AS WELL.  
 
..WENDT/THOMPSON.. 07/20/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...MQT...GRB...  
 
LAT...LON 46548988 47188889 46428704 45818661 45508680 45478777  
46548988  
 
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
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