Update on Severe Thunderstorm Watch 423 for northeast Illinois valid until Midnight CDT

Update 9:45PM CDT...

Kankakee County in Illinois and Newton, Jasper, Lake and Porter
Counties in Indiana have been added to the Watch that expires at
 Midnight CDT.
 
Winnebago, Ogle, Lee, Boone and DeKalb Counties have been
dropped from the Watch.
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Mesoscale Discussion 1357
   NWS Storm Prediction Center Norman OK
   0819 PM CDT Wed Jul 19 2017

   Areas affected...Northern IL...Southern WI

   Concerning...Severe Thunderstorm Watch 423...

   Valid 200119Z - 200245Z

   The severe weather threat for Severe Thunderstorm Watch 423
   continues.

   SUMMARY...Severe squall line will progress across central into
   eastern portions of WW423 over the next two hours.

   DISCUSSION...Long-lived MCS has cycled and matured into a
   fast-moving complex as it progresses across southern WI and northern
   IL. Latest radar data suggests the leading edge of a bow-shaped
   squall line is surging southeast at roughly 50kt. Given this
   speed/movement it appears the squall line will approach the
   northwestern Chicago metro between 0200-0230z, and the lake shore
   around 0230z. There is a possibility for widespread damaging winds
   along the leading edge of this convection.