Storm Prediction Center Mesoscale Discussion 248

   Mesoscale Discussion 0248
   NWS Storm Prediction Center Norman OK
   0516 PM CDT Sun Mar 15 2026

   Areas affected...Northeast Illinois-Northern Indiana-Southwest Lower
   Michigan

   Concerning...Severe potential...Watch needed soon 

   Valid 152216Z - 152315Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Severe Thunderstorm Watch will likely be issued soon for
   portions of northeast Illinois, northern Indiana, and southwest
   Lower Michigan.

   DISCUSSION...Leading edge of strongly forced squall line is
   advancing steadily east across western/northern IL. While low-level
   moisture is somewhat lacking downstream, with upper 40s/lower 50s
   surface dew points, cooling/moistening midlevel profiles favor weak
   destabilization over the next few hours. Strong shear supports
   damaging winds, and perhaps a brief tornado, with this forced line
   of convection and a Severe Thunderstorm Watch appears warranted.

   ..Darrow/Smith.. 03/15/2026

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

   ATTN...WFO...IWX...GRR...IND...LOT...ILX...

   LAT...LON   40978861 41628718 42098543 41458489 40678551 40458798
               40978861 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH