The EPA's Air Quality Index can tell you whether breathing outside air can be harmful. Here's how to read the scale to plan ...

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

Smoke from wildfires in Manitoba, a Western province facing its worst fire season in 30 years, has created hazardous air ...

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

Air pollution levels over Redding and parts of Shasta County are close to hazardous levels at times, due to heavy Green Fire ...

The extended forecast suggests unsettled weather midweek, with rain probabilities ranging from 30% to 60%. There is some ...

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

Smoke and haze could arrive in parts of the Bay Area on Friday thanks to wildfires in the northern portion of the state. The ...

Unhealthy air has invaded Minnesota, Wisconsin and North Dakota early this week as a new round of wildfire smoke from Canada ...

With wildfire smoke in the forecast, track the drop in air quality across dozens of PurpleAir sensors with our live, updating ...

Tuesday’s air quality warning has dropped to a 5, considered a moderate risk, down from Monday’s peak of 10+ on the Air ...

The smoke from Canadian wildfires produced some of the worst fine particle pollution on record in Minnesota over the weekend.