An air quality index of 300 or higher is considered hazardous, and the record-breaking smoke AQI in Grand Portage reached 800 ...

As Canadian wildfire smoke returns to the Chicago area, an air quality alert has been issued for most of the region. The Air Pollution Action Day was issued by the Illinois Environmental Protection ...

Smoke from a series of wildfires burning across central Canada has prompted officials to issue an air quality alert for the ...