Wildfire smoke leads to hazardous air quality across northern Wisconsin and the U.P. Wednesday

The Northwoods had among the worst air quality levels in the world Wednesday.

At their peak, air quality monitors in Ironwood and Crandon showed the PM 2.5 level exceed 600. PM 2.5 is fine-particle air pollution.

The ‘Hazardous’ level is between 301 to 500 PM 2.5. There is not level above that.

At these levels people are encouraged to stay indoors. Children, elderly, and those with underlying health conditions like asthma or heart disease are most at risk.

The smoke is coming from dozens of wildfires burning across northern Minnesota and Ontario. The fires burning Superior National Forest have led to the closure of the Boundary Waters.

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The view of the smoke from the roof of WXPR in downtown Rhinelander. Photo taken on Wednesday, July 15, 2026.

Galen Azbell/WXPR

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Wildfire smoke over the Wisconsin River.

Katie Thoresen/WXPR

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A screenshot of the Mt. Zion webcam. Wildfire smoke from Canadian and northern Minnesota fires block the view.

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A hazy Wednesday morning in Tomahawk.

Jessie Dick/WXPR

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Wildfire smoke over the Wisconsin River.

Katie Thoresen/WXPR

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A hazy Wednesday morning in Tomahawk.

Jessie Dick/WXPR

Have a photo of the smoke to share with WXPR?

Email it to news@wxpr.org.

The currently air quality alert that was issued Tuesday expires Thursday at noon. The Wisconsin DNR said at the time of issuing it could be extended beyond that. It is difficult to accurately forecast smoke more than 24-48 hour out.

Smoky summers have become more frequent for the Northwoods in recent years.

You can find resources on knowing your risk, ways to reduce smoke impacts, and get the latest air quality on the EPA’s AirNow website.