Chicago setting up for a wet and stormy night as severe thunderstorms approach the north portions of the Metro area

Mesoscale Discussion 1178
   NWS Storm Prediction Center Norman OK
   0753 PM CDT Wed Jun 28 2017

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

   Concerning...Tornado Watch 375...377...378...

   Valid 290053Z - 290230Z

   The severe weather threat for Tornado Watch 375, 377, 378 continues.

   SUMMARY...Severe threat continues.

   DISCUSSION...MCS continues to mature as it becomes elongated in an
   east-west fashion from northeast IA, east along the WI/IL border.
   This complex of storms is sagging south at roughly 15kt with an
   eastward surge on the order of 30kt along the leading squall line.
   Given this speed/movement, it appears strong convection will
   approach the northern Chicago metro between 0200-0230z and around
   0200z for the near-lake MI region of southeast WI. As the complex
   becomes oriented more east-west there will be a propensity for
   training across this region deep into the evening hours.