Mesoscale Discussion 1124
   NWS Storm Prediction Center Norman OK
   1154 AM CDT Tue Jun 29 2021

   Areas affected...Illinois...northwest Indiana...southern
   Michigan...and far northwest Ohio

   Concerning...Severe potential...Watch unlikely 

   Valid 291654Z - 291900Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Sporadic wind damage will be possible as storms develop
   during the late morning/early afternoon hours. Severe coverage
   should be limited, so a watch is not expected.

   DISCUSSION...GOES visible imagery shows a couple of developing
   thunderstorms and agitated cumulus along two outflow boundaries
   south/southeast of the Grand Rapids, MI area and across central to
   northeast IL. Ahead of these boundaries, a growing cumulus field has
   developed across eastern IL into IN and southern MI, indicative of
   diurnal destabilization. Further destabilization is expected through
   the afternoon as temperatures continue to rise in to the upper 80s
   low 90s amid dewpoints in the low 70s. Moderate instability (near
   2000 J/kg MLCAPE) will be in place along/ahead of these boundaries
   by early afternoon, and deep-layer shear over the region should
   remain sufficient for some organized convection. Regional VWP
   observations sampled 20 (35) knots of 0-3 km (0-6 km) shear, which
   will likely favor thunderstorm clusters along the boundaries through
   the early/mid afternoon. Sporadic wind damage will be possible,
   especially if cold pools can align orthogonal to the mean
   southwesterly flow/low-level shear vectors. Severe storms will
   likely be limited in coverage owing to the limited spatial overlap
   of favorable buoyancy and stronger winds aloft, so a watch is not
   likely.

   ..Moore/Thompson.. 06/29/2021

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

   ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...LOT...ILX...

   LAT...LON   40188896 41138791 41868687 42398616 42628525 43328363
               43188264 42928229 42378261 41808308 41418347 40948414
               40458505 40018603 39628697 39508756 39788898 40188896