Here's everything to know about today's weather. What is an air quality alert? According to Columbia University, the EPA created the air quality index, or AQI, "to monitor and report on air ...

Smoke from Canadian wildfires is causing air quality concerns for millions of Americans in the Midwest and Northeast.

Over the past five years, as California wildfires increased in both intensity and scope, Bay Area skies have intermittently filled with smoke, causing residents to routinely check the air quality ...

Olympic and Mount Rainier national parks are among areas with closures as smoke from nearby wildfires makes the air quality ...

A cold front brings thick wildfire smoke to Colorado, causing Denver to have the worst air quality in the U.S.

The agency said fires burning in parts of the Inland Northwest are playing a factor in the deteriorated air quality.

Smoke from wildfires outside Baker County is keeping the air quality in the moderate category in Baker City, although ...