Multiple U.S. states and Canadian provinces are experiencing poor air quality from wildfire smoke. Here's where.

The Cram fire is the largest in the state, expanding overnight to more than 64,000 acres, according to the Northwest ...

The National Weather Service has issued both a heat and air quality alert for most of downstate New York, Wednesday, July 16.

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 ...

Sensitive groups are advised to stay indoors and limit outdoor activities as pollution and ozone levels spike to unhealthy ...

EDT on Tuesday, the National Weather Service reported an air quality alert in effect until Thursday at midnight EDT for ...

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

At 9:13 a.m. on Wednesday, the National Weather Service reported an air quality alert in effect until Thursday at midnight ...

An updated air quality alert was reported by the National Weather Service on Tuesday at 4:13 a.m. EDT in effect until ...

The National Weather Service reported an air quality alert at 3:46 p.m. on Tuesday in effect until Wednesday at 11:15 p.m.

This week in the Boston Globe Weather Mailbag, Globe Weather HQ tackles questions surrounding summer thunderstorm frequency, ...