Is the air quality good in the Great Lakes Region?

As of July 15, 2025, there is poor air quality due to wildfire smoke across many U.S. states and Canadian provinces, mostly in the lower Great Lakes region.

Smoke is contributing to poor air quality ranging from the “moderate” to “unhealthy” range in Illinois, Indiana, Michigan, Minnesota, Ohio and New York.

In Canada, poor air quality is unhealthy in major cities across Ontario and Quebec, as well as parts of Manitoba and Saskatchewan. As of the morning of July 15, Montreal, Canada was the sixth most polluted major city in the world. Detroit, Michigan was the 7th and Toronto, Canada was the 10th.

Ranked list of most polluted major cities on Tuesday morning. Source: IQAir.

Which major cities are most affected by the poor air quality today?

Major cities affected by wildfire smoke include:

• Buffalo, New York
• Chicago, Illinois
• Cleveland, Ohio
• Detroit, Michigan
• Duluth, Minnesota
• Minneapolis, Minnesota
• Montreal, Quebec
• Saskatoon, Saskatchewan
• Toledo, Ohio
• Toronto, Ontario

What is causing poor air quality in the Great Lakes Region?

Widespread wildfires across northern Canada and shifting wind direction has sent smoke southeast towards the Great Lakes Region and the St. Lawrence River.

Are there any alerts in place?

The National Weather Service has issued Air quality alerts for southeast Michigan, northeastern Illinois, northern Vermont and Maine, most of New York, northern Minnesota, and northeastern Indiana (1). There is also a poor air quality warning in Toronto, Ontario and most of central Ontario (2).

How can I protect myself from poor air quality?

• Get a free air quality app for real-time air quality alerts and forecasts.
• Shut doors and windows and set the HVAC to recirculate mode.
• Contribute to your community’s outdoor air quality data.
• Stay indoors when air quality is poor; if you do need to go outdoors, wear a KN95/FFP2 mask.
• Run a high-performance air purifier to filter particles, gases, and other pollutants.