Smoke from ongoing wildfires across Canada continued to drift into parts of the United States on Wednesday, causing hazy skies and triggering air quality alerts in multiple states across the upper Midwest and Northeast.

On Aug. 6, the Wisconsin Department of Natural Resources has not extended its Wisconsin air quality alert — a decision it hasn't made in over a week.

Hundreds of wildfires still burning in Canada are expected to undermine air quality across the Upper Midwest and Northeast into Tuesday.