The annual Chicago River Swim was canceled early Sunday as heavy rainfall continued to pummel the Chicago area.
Race organizers said the potential for sewer overflow impacting water quality and the risk for lightning contributed to their decision to cancel. It would have been the second Chicago River race in nearly 100 years.
The National Weather Service issued a flood advisory early Sunday as forecasters expect the rain to continue into Monday. Heavy rainfall and thunderstorms started Saturday across the Chicago region.
The average flight delay was 19 minutes, and 56 flights were canceled at O’Hare International Airport Sunday, according to the Chicago Department of Aviation. At Midway International Airport, one flight was canceled and the average delay was 20 minutes.
Day two of Riot Fest was cut short Saturday because of “torrential downpours,” and the fest opened its grounds late and altered its schedule Sunday.
Rain chances will persist through Monday, though threat of heavy rainfall should end by early this afternoon. Dry, but cooler than average weather can be expected by mid-week. #ILwx #INwx pic.twitter.com/v86GOTOB33
— NWS Chicago (@NWSChicago) September 20, 2026