The Chicago area recorded ozone levels of 156 late Monday afternoon. Levels above 100 are considered unhealthy. Residents ...

Sensitive groups are advised to stay indoors and limit outdoor activities as pollution and ozone levels spike to unhealthy ...

The Illinois Environmental Protection Agency has issued an Air Pollution Action Day for Tuesday, July 15. Here's what to know ...

The 'unhealthy for sensitive groups' air quality in Chicago comes as an air quality alert was issued for the entire state of ...

Air quality in the Chicago area has remained poor for three days in a row, the NBC 5 Storm Team reported Wednesday morning.

An Air Quality Alert has been issued through Tuesday for the Chicago area from wildfire smoke coming in from Canada.

Today is warm with an air quality alert in effect. Sensitive groups should take it easy again as we have elevated ozone ...

CHICAGO (WLS) -- An air quality alert was extended through Wednesday by the National Weather Service for the Chicago area.

An Air Quality Alert remains in effect until midnight Tuesday night for several Chicago-area counties. Here's what to know.

The National Weather Service’s Chicago office attributed the alert to unhealthy ozone levels and lingering effects of smoke from wildfires in Canada.

The Illinois EPA declared an Air Pollution Action Day in the Chicago metro area. See today's air quality index forecast for Illinois.

Chicago faces a heat wave with poor air quality due to wildfire smoke and ozone; temperatures may hit mid-90s.