Overview

• Air quality alerts remain active in more than a dozen Midwestern and Northeastern states, with PM2.5 levels classified as unhealthy for sensitive groups.
• Over 700 wildfires, many of them out of control, are currently burning across Canada, according to the Canadian Interagency Forest Fire Centre.
• A high-pressure ridge has trapped dense smoke near the surface, prolonging poor breathing conditions in cities such as Detroit and Minneapolis, which have ranked among the worst in global air quality.
• Health officials advise vulnerable populations—including children, older adults, and people with asthma or heart conditions—to limit outdoor activities and use air purifiers or masks.
• Meteorological models predict that shifting winds later this week will push the smoke largely back into Canada, potentially clearing skies by Thursday or Friday.