Storm Prediction Center Mesoscale Discussion 191

   Mesoscale Discussion 0191
   NWS Storm Prediction Center Norman OK
   0453 PM CDT Tue Mar 10 2026

   Areas affected...portions of eastern Iowa into northern Illinois and
   southwestern lower Michigan.

   Concerning...Severe potential...Watch likely 

   Valid 102153Z - 102330Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Scattered elevated supercells and bowing segments appear
   likely this afternoon/evening north of the east-west warm front. A
   risk for significant hail and damaging gusts is possible. A WW is
   likely needed shortly.

   DISCUSSION...As of 2145 UTC, mesoanalysis and radar observations
   showed an east-west oriented warm front stretching from eastern IA,
   across northern IL into southern lower MI. South of the front,
   temperatures in the 70s and 80s F amid mid to upper 60s F surface
   dewpoints are supporting moderate to large buoyancy of 2000-3000
   J/kg of MLCAPE. Strong destabilization is also ongoing in an
   elevated manner along and north of the boundary with 1500-2500 J/kg
   of MUCAPE despite cooler surface temperatures. Strong mid-level flow
   is overspreading the boundary supporting deep veering wind profiles
   supportive of organized severe storms.

   Weak surface convergence southeast of the front has ignited several
   supercells across northern IL this afternoon. As storms cross out of
   the Tornado Watch and the front, they will become elevated. With
   robust buoyancy and deep-layer shear greater than 50 kt, they are
   likely to remain intense and capable of large to very large hail.
   Recent CAM guidance and surface convergence near a surface low in
   IA/MO suggest numerous storms will develop within the elevated
   regime over the next few hours. 

   With time, these initial supercells are likely to grow upscale into
   elevated bows or clusters with a continued hail threat and possibly
   damaging winds associated with strong gravity waves propagating
   along the top of the stable surface layer. Given the increasing
   severe threat, a new WW is likely needed for eastern IA into
   northern IL and portions of western lower MI.

   ..Lyons/Hart.. 03/10/2026

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

   ATTN...WFO...IWX...GRR...LOT...MKX...DVN...

   LAT...LON   41359124 41339201 41879171 42459083 42598948 42718788
               42738720 42758604 42728566 42238543 41928552 41688609
               41378815 41359124 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN