The summer of 2025 has brought some of the worst air quality ever recorded to large parts of the United States. Cities across the Midwest and Northeast—especially Chicago, Detroit, Cleveland, New York City, Boston, and Philadelphia—are under siege from thick smoke drifting south from Canadian wildfires, according to an August report from NPR.
The Environmental Protection Agency has issued Code Red and even Purple Air Quality Alerts for these urban centers. On the worst days, levels of dangerous particulate matter (PM2.5) have soared far above safe limits, forcing state and local governments to close parks, cancel outdoor events, and urge residents to stay inside. Vulnerable groups—children, the elderly, and those with respiratory illnesses—face the highest risks.
