More than 80 million Americans across the country began June 28 with unhealthy air quality alerts due to intense smoke coming from Canadian wildfires.
By the end of the day, the number of Americans affected was more than 120 million. The smoke plagued the Midwest and parts of the East Coast.
There are an estimated 500 wildfires burning in Canada, making this the worst wildfire season on record with the highest smoke emission rates.
Air quality advisories are still being issued across the United States. Experts say there is a chance the smoke will get worse.