Gusty winds up to 55 mph, along with short downpours, are possible overnight Tuesday across the southwest suburbs and South Side.
The strong winds are likely to cause hazardous conditions on Lake Michigan, with choppy waves between 2 and 4 feet, the National Weather Service said. That’s created a “moderate swim risk” for Wednesday afternoon into Thursday morning on southern Lake Michigan beaches.
Wednesday will see a 30% chance of rain, with partly cloudy skies, a high of 84 and a low of 67. No rain is expected Thursday. Another chance of showers and thunderstorms is forecast for Friday and Saturday, the weather service said.
A flood advisory was briefly issued for parts of Cook and Will counties Tuesday evening as thunderstorms brought downpours into the area.
The flood advisory was in effect until 6 p.m. for southern Cook County and eastern Will County, according to the weather service. Some of the flooding could reach the South Side of Chicago, but most other areas of the city were not at risk.
“These [storm] cells are efficient rainfall producers, 1 to 2 inches of rain per hour, so can’t rule out some localized ponding, collection of water in low spots, dips, typical flood-prone areas,” NWS meteorologist Lee Carlaw said.
Thunderstorm coverage has trended down over the last hour or so, however, isolated storms continue and are even redeveloping into parts of the SW suburbs. We are also monitoring storms up in Wisconsin that may drift into portions of NW Illinois later this evening. #ILwx #INwx pic.twitter.com/ZPScNSvEZX
— NWS Chicago (@NWSChicago) July 9, 2025
More rain is expected throughout the week, but likely not enough to produce significant flash flooding, Carlaw said.
“The thing with flooding in the city is that basically, any thunderstorm that produces an inch or 2 inches of rain tends to cause localized flooding issues,” Carlaw said. “There’s a very limited infiltration because of all the concrete and so that runoff could lead to what we call urban flooding … but it’s not the type of flooding that’s going to be sweeping away cars.”