ACUS11 KWNS 182152

SWOMCD

SPC MCD 182152 

MIZ000-WIZ000-182345-



Mesoscale Discussion 2028

NWS Storm Prediction Center Norman OK

0452 PM CDT Tue Aug 18 2026



Areas affected...northern lower Michigan Peninsula



Concerning...Severe potential...Watch possible 



Valid 182152Z - 182345Z



Probability of Watch Issuance...40 percent



SUMMARY...Large hail and damaging wind will be possible with

isolated supercells this evening.



DISCUSSION...Thunderstorm activity is shifting eastward across Lake

Michigan this evening. Downstream, the air mass is only marginally

unstable, with MLCAPE around 250-500 J/kg. Deep layer flow is

seasonably strong, with deep layer shear 35-45 kts across the

northern lower Michigan Peninsula. RAOB profiles from APX (Gaylord,

MI) shows a long straight hodograph, which would be supportive of

splitting supercells capable of large hail and damaging wind.

Damaging wind potential may be further supported by steep low level

lapse rates (around 8 C/km). There remains some uncertainty with how

long supercells will be sustained, given the only marginally

favorable thermodynamics. This area will be monitored for watch

potential.



..Thornton/Gleason.. 08/18/2026



...Please see www.spc.noaa.gov for graphic product...



ATTN...WFO...DTX...APX...GRR...MQT...GRB...MKX...



LAT...LON   44878784 45708653 46048525 46048401 45588292 45038228

            44148251 43428347 43398547 43448661 43768773 44278801

            44878784 



MOST PROBABLE PEAK WIND GUST...55-70 MPH

MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN