Mesoscale Discussion 1287
   NWS Storm Prediction Center Norman OK
   0542 PM CDT Wed Jul 14 2021

   Areas affected...Eastern IA...Northern IL...Southern WI

   Concerning...Severe potential...Watch likely 

   Valid 142242Z - 142345Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Severe threat is increasing across eastern IA/northwestern
   IL into southern WI. New ww will likely be warranted soon.

   DISCUSSION...Early-day MCS has progressed across the upper Midwest
   with the leading edge now spreading across LE. Considerable
   boundary-layer disruption has been noted across WI/northern IL into
   extreme northeast IA. However, over the last few hours, partial
   clearing across eastern IA has allowed surface temperatures to warm
   into the lower 80s from east of ALO-MXO-CWI-north of C75 in
   Illinois. Further recover appears likely to near the WI/IL border
   over the next few hours. While updrafts may struggle to be truly
   surface-based where temperatures struggle to rise above 75F, there
   is increasing concern/confidence that ongoing supercells over
   central IA will progress east of ww378 into a region that is
   recovering in the wake of earlier convection. Ample shear/buoyancy
   suggest supercells will continue, along with a tornado threat.
   Additionally, LLJ is forecast to increase across southern/central WI
   this evening and this should encourage renewed convective
   development. New ww will likely be issued soon.

   ..Darrow/Guyer.. 07/14/2021

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

   ATTN...WFO...LOT...MKX...DVN...ARX...

   LAT...LON   43269164 43638913 42848852 42168919 41829151 43269164