As Canada grapples with one of its worst wildfire seasons on record, smoke from the blazes have prompted air quality alerts across the U.S.

Smoke from Canadian wildfires is causing air quality concerns for millions of Americans in the Midwest and Northeast.  Air quality alerts were in effect Tuesday in several states, including Michigan and New York.

Wildfire smoke brings hazy skies and poor air quality to Chicago today, with hot and humid weather building into the weekend.