Canadian Wildfire Smoke Triggers Air Quality Alerts in 20-Plus U.S. States

On July 16, 2026, smoke from nearly 850 active Canadian wildfires — over 180 in northern Ontario alone — spread across the U.S., triggering air quality alerts in more than 20 states from Minnesota to North Carolina. Toronto's air quality briefly ranked among the world's worst on July 15. Millions of Americans face unhealthy PM2.5 levels as winds carry the plume southeast.