There is a Flood Warning for Kane, Lake, McHenry, Kendall and LaSalle counties in Illinois until 5:30 a.m. Friday.
There's a Flood Warning for Cook County until 5:15 a.m. Friday.
There's a Flood Watch for Lake County, Indiana until 5:30 a.m. Friday.
Firefighters spent the day fortifying a station prone to flooding as the city provides sandbags for people to help protect their homes.
Authorities in Lake County, Illinois already issued a warning that parts of the river could overflow after recent storms saturated the ground, making some roads impassable.
"You want to stay out of the flood waters," Des Plaines Fire Chief Matt Matzl said. "We don't want to walk in it. We don't want to drive in it. It's contaminated water first of all. So it's unhealthy. And if we're driving, we want to stay out of it. Even 12 inches of water, a car could get washed away; so we want to stay out of that."
People can pick up sandbags over at Public Works.
The Des Plaines River is expected to crest Friday. But officials say after the storms move through, warm weather should allow water levels to recede.
Spotty showers are expected Thursday.
There was a ground stop at O'Hare airport due to thunderstorms Thursday morning.
A Ground Delay is in effect until about 7 p.m.
More severe weather is possible Friday evening.
Severe storms possible Friday after days of rain
After a potentially dense fog burns off, temperatures will rise to 80 Friday.
Storms are possible between about 7 p.m. and midnight. High wind is the main concern, but some brief tornadoes could be possible.
The Chicago area is under a Level 2 risk of severe weather, with a 2% tornado threat.