The north suburbs saw the brunt of the damage, especially in Morton Grove and Glenview.
Morton Grove police said trees were down in the area of Greenwood Street and Mamora Avenue. In Skokie, at least one large tree fell and blocked the road on Kilbourne Avenue.
The downed trees and branches damaged at least one car and pulled own power lines.
In Glenview, a house fire is being investigated as possibly started by a lightning strike, though officials have not yet confirmed that.
ComEd said as of 8:30 p.m. about 3,930 customers were without power.
The heavy rains prompted a Flash Flood Warning in Boone and McHenry counties for several hours, though downpours were widespread and stretched all the way into downtown Chicago.
And round of scattered storms are expected Wednesday.