The Illinois Environmental Protection Agency has issued an Air Pollution Action Day for the Chicago Metropolitan area for Wednesday, May 27 due to elevated ozone pollution. The Action Day includes the counties of Cook, DuPage, Kane, Kendall, Grundy, Lake, McHenry and Will. Regional air quality is expected to reach the “Unhealthy for Sensitive Groups” (USG)/Orange category on the national Air Quality Index (AQI) today, May 26th, and is expected to extend into tomorrow, May 27th. This is the first Action Day issued by Illinois EPA for 2026.
Hourly NowCast AQI readings may show higher categories than what is forecast to help identify periods of higher 1-hour ozone. Those with air quality concerns can check current NowCast readings or sign up for EnviroFlash alerts on AirNow.gov.
In Illinois, a Chicago Air Pollution Action Day is issued when air quality is forecasted to be at or above the USG/Orange category for two or more consecutive days for Chicago Metropolitan area. Elevated ozone levels are expected to continue impact the area with 8-hour AQI forecast for ozone at the USG/Orange level on May 26th and 27th, posing a potential health hazard to sensitive populations. Individuals most at risk due to elevated air pollution, including ground-level ozone and particle pollution, are those with respiratory or pulmonary disorders, as well as children and adults who are active outdoors. Sensitive individuals should follow their doctor’s advice. Some symptoms to look out for include wheezing, coughing, a fast heartbeat, fatigue, chest pain, and shortness of breath. If symptoms worsen, you should call your physician or 911…