Wildfire smoke from blazes in Canada and northern Minnesota has pushed across the Midwest and into the Northeast this week, triggering hazardous air quality alerts and emergency responses in major cities. Chicago's air quality ranked second-worst in the world on Friday, while parts of Michigan, Ohio, and Wisconsin recorded Air Quality Index ratings in the 300s.
The National Weather Service issued unhealthy-to-hazardous smoke maps across multiple states as more than 800 wildfires burned across Canada and thousands evacuated in Ontario and northern Minnesota. New York launched emergency operations distributing free KN95 masks, and Philadelphia suspended trash collection and closed public pools. Millions of Americans are simultaneously under heat advisories as temperatures exceed 100 degrees in the Great Lakes region, Pennsylvania, and Virginia.
Nearly 3.72 million acres have burned across the U.S. in 2026, surpassing last year's mid-July total by more than a million acres, with over 17,400 personnel battling fires nationwide.