"It is recommended that, when possible, you avoid strenuous outdoor activities, especially those with heart disease and ...

Smoke from Canadian wildfires persisted across the Upper Midwest on Friday, prompting air quality alerts for millions.

Officials warn southeast Michigan residents to be careful outdoors Tuesday because of expected high ozone pollution levels.

Air quality, smoke and ozone alerts are in effect for much of the state heading into a hot, smoky weekend. A red flag warning ...

Besides temperatures feeling in the high 90s, Chicago and surrounding areas are under an air quality alert until midnight, ...

A special weather statement and warning have been issued for southern Ontario on Wednesday. The heat warning continues with temperature highs around 32 C or 40 C with the humidex in the Greater ...