National Weather Service officials called an air quality alert in effect until midnight as well as a beach hazard warning.

National Weather Service officials issued an air quality alert set to expire at midnight Saturday for the Chicago and ...

Wildfire smoke from Canada turned Chicago into one of the world’s most polluted metro areas as the Lollapalooza music ...

"The air quality is officially dangerous in Chicago," says Brian Urbaszewski, director of environmental health programs at ...

Wildfire smoke has pushed Chicago's air quality into the "unhealthy" zone. It's so bad, in fact, that we're the most polluted ...

The National Weather Service has opted to extend an air quality alert in the Chicago area for another day.

While air quality was in the "unhealthy for sensitive groups" category in Chicago, it was even worse in some suburbs.

Most of the Chicago area remains under an Air Quality Alert this weekend due to smoke from Canadian wildfires.

Chicago had the worst air quality in the world for a few hours Thursday, thanks to smoke from Canadian wildfires.

Health officials from Minnesota to Maine have issued alerts warning of poor air quality from wildfires burning in Canada.

Chicago officially had the worst air quality in the world for a few hours Thursday. As a haze of Canadian wildfire smoke ...

Several wildfires burning across the northwestern Canadian provinces are again sending vast amounts of smoke into the upper Midwest and northeastern US, swamping the area with unhealthy air quality – ...