Storm Prediction Center Mesoscale Discussion 913

   Mesoscale Discussion 0913
   NWS Storm Prediction Center Norman OK
   0551 PM CDT Tue May 20 2025

   Areas affected...Parts of east-central Illinois and west-central
   Indiana

   Concerning...Severe Thunderstorm Watch 304...

   Valid 202251Z - 202345Z

   The severe weather threat for Severe Thunderstorm Watch 304
   continues.

   SUMMARY...The tornado threat is likely peaking now (as of 2245Z),
   and should lessen with northeastward extent over the next hour.

   DISCUSSION...A supercell with a history of producing tornadoes (and
   a couple upstream cells) are tracking eastward toward the cool side
   of a warm front, though they are still in a very localized corridor
   of surface-based instability and 150-200 m2/s2 effective SRH.
   Therefore, the tornado threat is likely peaking now with this
   activity, before it moves to the cool/stable side of the boundary.

   ..Weinman.. 05/20/2025

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

   ATTN...WFO...IND...LOT...ILX...

   LAT...LON   40068795 40368811 40608783 40688744 40558723 39998677
               39708696 39718730 40068795 

   MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN