Canadian wildfire smoke is triggering air quality alerts across the U.S. Midwest and Northeast on Thursday, as the northern nation’s boreal forests continue to burn at a rate not seen except for a historic season in 2023.

Smoke from wildfires in Canada continues to drift into New York, leading officials to declare another Air Quality Health Advisory for Thursday.

The alert advises "sensitive groups" — including individuals with asthma or heart disease — to participate only in shorter and less intense outdoor activities.