Storm Prediction Center Mesoscale Discussion 798

   Mesoscale Discussion 0798
   NWS Storm Prediction Center Norman OK
   0650 PM CDT Thu May 15 2025

   Areas affected...Parts of western/central Lower Michigan into
   northern/central Indiana

   Concerning...Severe potential...Watch likely 

   Valid 152350Z - 160115Z

   Probability of Watch Issuance...80 percent

   SUMMARY...A line of severe storms capable of producing embedded
   tornadoes, damaging winds, and large hail will overspread the area
   from the west into tonight. One or more watches will likely be
   issued for parts of the area.

   DISCUSSION...A broken band of severe storms, including several
   embedded supercell structures, is tracking eastward across far
   eastern Wisconsin -- posing an all-hazards severe risk. As an
   occluded surface front continues eastward, this line of storms, and
   potentially new storms in the pre-frontal warm-advection plume, will
   overspread western/central Lower MI and northern/central IN over the
   next few hours. Earlier diurnal heating of a moist boundary layer
   (middle/upper 60s dewpoints) beneath steep midlevel lapse rates is
   contributing to moderate/strong surface-based instability. In
   addition, 40-50 kt of effective shear oriented mostly perpendicular
   to the ongoing convection will support a band of severe storms with
   embedded supercells and bowing structures. Ample low-level SRH will
   support embedded tornadoes, with damaging winds and isolated large
   hail also possible. One or more watches will likely be issued for
   the area.

   ..Weinman/Gleason.. 05/15/2025

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

   ATTN...WFO...DTX...APX...IWX...GRR...IND...LOT...

   LAT...LON   44458636 44738597 44788540 44628480 44258429 43418422
               42028446 40508504 39818560 39728612 39748671 40018742
               40398740 42278668 43388668 44048663 44458636 

   MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN