It was quite an active weather day in the Chicago metro area and Midwest on Friday. We started out with an area of storms moving through the metro area about mid morning. The storms were weakening at that point so rainfall was only a few tenths of an inch. By the time the storms reached north central Indiana, there had been enough heating ahead of the storms to intensify the storms to severe levels. The area from northeast Indiana through northwest Ohio was hit very hard with a lot of wind damage including blown off roofs and siding. Radar showed a broad area of wind speeds of 80-90 knots (~90-100+ mph) above the surface. A gust to 91 mph was recorded at Fort Wayne airport. A list of the storm reports received by the North Webster NWS office can be found here. This thunderstorm complex or Derecho continued east through the day all the way to Washington DC and the coast leaving millions without power. A map of storm reports can be found here.
A second area of showers and storms formed over central Iowa late afternoon. The area moved east around 30 knots producing a few severe reports along the way from eastern Iowa into northwest Illinois. As a small storm line moved out of DeKalb county it turned a little southeast to feed off the better moisture and instability that sat just south of the metro area. Suddenly in the Oswego/Yorkville area the storm line transformed itself into basically a small ball. Winds suddenly jumped up to 80-90 knots (~90-100+ mph). The picture on the left shows the concentrated storm just west of Plainfield with 84 knots (~96 mph) of wind only 400 feet above the surface. Wind damage was reported from the Yorkville area through Plainfield into Romeoville, finally ending around Orland Park. The storm produced a 87 mph wind gust at the NWS office in Romeoville. A list of northern Illinois storm reports can be found here.
Looking ahead, there is no real break in the heat through the coming week. Every day looks to be somewhere in the low to mid 90s through the week except lakeside areas. Would not be surprised that by mid week we are in the 95-100 range as upper level riding takes hold. Scattered storms look possible today south of I80. For Sunday through Tuesday the humidity will creep north again. With weak upper level disturbances forecast to move over the area each day, and weak lake breezes to act like mini fronts, each afternoon/evening will see scattered small clusters of storms somewhere over northern Illinois into southern Wisconsin. Hopefully, one of those clusters will provide more rain at your place.
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