States Issue Air Quality Warnings Over Smoke from Canadian Wildfires
August 4, 2025
Health officials across multiple U.S. states have issued air quality alerts as thick smoke from Canadian wildfires drifts southward, creating hazardous conditions in regions from the Midwest to the Northeast. The alerts, in effect from Minnesota to Maine, urge residents to limit outdoor exposure due to high levels of fine particulate matter (PM 2.5), which can penetrate deep into the lungs and pose significant health risks.
The Canadian Interagency Forest Fire Centre reported over 700 active wildfires burning across Canada on August 3, 2025, with more than 500 classified as out of control, primarily in Manitoba, Ontario, and Saskatchewan. This marks Canada’s second-worst wildfire season on record, with nearly 4,000 fires recorded this year, forcing thousands to evacuate. The smoke has significantly impacted air quality in the U.S., with states like Minnesota, Wisconsin, Iowa, Michigan, Illinois, and parts of the Northeast experiencing “unhealthy” to “very unhealthy” conditions on the Air Quality Index (AQI). Minneapolis, in particular, ranked among the world’s worst cities for air pollution on August 1, with AQI levels reaching the “red” category, indicating health risks for all residents, especially vulnerable groups like children, the elderly, and those with respiratory or heart conditions.
Minnesota’s Pollution Control Agency issued its longest air quality alert since 2008, extending through August 3, with conditions expected to improve slightly by Monday but potentially worsen again next week. The agency warned of symptoms such as irritated eyes, coughing, and shortness of breath, even in healthy individuals. In Iowa, a statewide alert remains in effect through early Thursday, advising residents to avoid strenuous outdoor activities. Similar advisories are active in New York, New Jersey, New Hampshire, and Maine, with New York City’s AQI reaching 120-136, classified as “unhealthy for sensitive groups.”
The smoke, driven by strong winds and dry conditions, has created hazy skies and reduced visibility across affected areas. In Chicago, the Illinois Environmental Protection Agency declared a Red Air Pollution Action Day for several counties, urging caution. Health officials, including Dr. Chase Shutak of Children’s Minnesota, reported a modest increase in patients with respiratory issues, such as asthma and breathing problems, due to the polluted air.
Experts recommend staying indoors, keeping windows closed, using air purifiers with high-quality filters, and wearing N95 or KN95 masks when outside. The National Weather Service noted that while smoke is expected to linger over the northern and central Plains for the next few days, some areas may see temporary relief by mid-week. However, meteorologists warn that Canada’s wildfire season, exacerbated by climate change, could continue to impact U.S. air quality for weeks.
For real-time air quality updates, residents are encouraged to visit AirNow.gov or download the EPA’s AirNow mobile app.