ZCZC SPCSWOMCD ALL
ACUS11 KWNS 301838 
SPC MCD 301838 
INZ000-ILZ000-WIZ000-302045-

Mesoscale Discussion 1315
NWS Storm Prediction Center Norman OK
0138 PM CDT Sun Jun 30 2019

Areas affected...IL

Concerning...Severe Thunderstorm Watch 466...

Valid 301838Z - 302045Z

The severe weather threat for Severe Thunderstorm Watch 466
continues.

SUMMARY...Severe threat will spread south across ww466 over the next
several hours. Damaging winds remain the primary threat.

DISCUSSION...Long-lived MCS that developed over northern MN/WI has
progressed into northern IL where boundary-layer heating appears to
be aiding renewed updraft development along/ahead of the leading
squall line. 18z ILX sounding exhibited significant warming at 700mb
with notable CINH still present early this afternoon. However,
satellite imagery suggests an expanding boundary-layer cu field with
deepening thermals along a boundary that is draped from
south-central IN into north-central IL ahead of the MCS. This
corridor of cumulus is the most likely path of propagation for the
MCS as it spreads southeast. Additionally, winds have recently
gusted to 55kt at KRFD and this is further evidence that the MCS has
likely matured to the point it will continue well into the late
afternoon.

..Darrow.. 06/30/2019

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

ATTN...WFO...IND...LOT...ILX...MKX...DVN...

LAT...LON   42699021 42698786 40348742 40348970 42699021 

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