Wildfire smoke degrades air quality in swaths of Ontario, with Toronto ranking among the worst in the world on Monday.

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

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

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

Meteorologist David Yeomans has the extended forecast.

The air quality is poor today in northern Illinois due to migrating Canadian wildfire smoke. See the AQI in your area.

CHICAGO (WLS) -- An air quality alert was issued by the National Weather Service for the Chicago area. Chopper 7 captured as ...

An air quality alert in the Chicago area will stretch into a third day as pollutants continue to linger in the air at high ...

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

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