Storm Prediction Center Mesoscale Discussion 1068

   Mesoscale Discussion 1068
   NWS Storm Prediction Center Norman OK
   0206 PM CDT Wed Jun 10 2026

   Areas affected...central Illinois and the vicinity

   Concerning...Severe Thunderstorm Watch 301...

   Valid 101906Z - 102000Z

   The severe weather threat for Severe Thunderstorm Watch 301
   continues.

   SUMMARY...A line of thunderstorms is moving across WW301 and
   portions of northern/central IL. It may pose a threat for wind gusts
   and small hail during the afternoon. Watch issuance/extension may be
   needed to address this scenario.

   DISCUSSION...A large mesoscale convective system (MCS) continues to
   move east/northeastward across WW301 and portions of WI and IL. An
   expansive stratiform region is evident in regional radar imagery,
   and the cold pool is likely characterized by deficits around 10 F
   based on surface observations. A 64-kt gust was reported at 1740z in
   association with the bowing portion of the MCS currently moving
   northeastward into WI (northwest of the delineated region in this
   MCD). The southern portion of the MCS has been relatively less
   organized than its northern counterpart, probably owing to less deep
   ascent driven by less-line-orthogonal bulk shear. It is currently
   moving through the regional CAPE axis, characterized by MLCAPE
   around 2000-2500 J/kg, and the leading line has shown some recent
   uptick in convective organization (particularly in central IL). The
   18z ILX sounding depicts a relatively uninhibited environment with
   around 30 kts of effective shear. This lends increasing confidence
   in some coverage of severe wind gusts and hail as the MCS propagates
   through central IL. Watch issuance/extension is being considered to
   address this scenario.

   ..Flournoy/Mosier.. 06/10/2026

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

   ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN...

   LAT...LON   39169049 39489188 39969064 41038986 41768954 42208874
               42148784 41628715 40358707 39448837 39169049 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN