Chicago area under flood watch Friday night through Saturday morning

The Chicago area could see more flooding as heavy rainfall is expected Friday night into Saturday morning, according to the National Weather Service.

A flood watch is in effect for much of the Chicago area, especially south of Interstate 80, from 10 p.m. Friday through 10 a.m. Saturday, according to the weather service. Water from creeks and streams could rise out of their banks, and urban areas with poor drainage could also flood in Chicago and suburbs as far as Naperville and Calumet City.

The flood watch comes as the Chicago area has seen some of the most severe storms in recent memory this summer, which have caused damage to homes, widespread flooding and, for the first time, nearly filled the reservoirs meant to manage stormwater and flooding. The effects of storms can be cumulative, and flooding can happen even with small amounts of rain if the ground has already had to handle a lot of water, according to weather service meteorologist Brett Borchardt.

“That’s what’s setting the table for the potential flash floods tonight,” Borchardt said. “The ground is really saturated and can’t really take much water.

Central Illinois is likely to see the worst of the storm impact because the area got heavy rain Thursday night, Borchardt said. Chicago and the northern suburbs are still likely to see rain and storms, but the further south you get, the more rain and flooding are possible, he said.

“The threat for rain is higher down there. [I] wouldn’t be surprised if folks wake up to some rumbles of thunder as early as 3, 4 in the morning,” he said.

A flood watch was issued for the area earlier this week. Residents in the south suburbs and northwest Indiana are still grappling with the effects of tornadoes and other severe storms from earlier in the summer.