Wildfires expose millions in the Midwest and Northeast US to dangerous smoke

New York — Thick smoke from several large wildfires burning in Canada and Minnesota is expected to sweep across large swaths of the Midwest and northeastern United States this week, exposing millions of people to dangerous air pollution.

Minnesota officials issued an air quality alert Tuesday through Friday for areas including the Twin Cities metro area, Alexandria and Two Harbors, with very heavy smoke expected in the northeast corner of the state as large wildfires spread. Air quality levels in Two Harbors, the Grand Portage Tribal Nation and other areas in northeastern Minnesota were expected to reach dangerous levels, making them unsafe for everyone.

Extreme drought conditions combined with heat in Canada and the United States have created “a perfect storm for really dry conditions to provide a lot of fuel to fuel these wildfires,” said Dan Westervelt, an assistant professor at Columbia University’s climate school. Research shows that rising temperatures caused by burning coal, oil and gas are making fires more frequent and severe.

People should stay indoors as much as possible to avoid extreme heat, especially as smoke moves, said Tyler Hassenstein, a meteorologist with the National Weather Service in Chanhassen, Minnesota.

“These two things coexisting together is not good from a health standpoint,” he said.

Officials in Michigan and Wisconsin warned residents Tuesday of air quality issues that could last for several days. High levels of fine particulate matter in the air from wildfire smoke may be unhealthy for sensitive groups, such as children and people with heart or lung disease.

In parts of Maine, residents reported a yellow and brown color appearing in the sky. “There is a lot of smoke upstream, so expect periods of hazy skies over the next day before the cold front passes,” the National Weather Service in Gray, Maine, said on social media Tuesday.

By Wednesday afternoon, heavy smoke will spread across the East Coast and Midwest, including parts of coastal New England, northern Pennsylvania, Detroit and Milwaukee, Hassenstein said.

Multiple counties in western and central New York were under an air quality advisory Wednesday until midnight. Hassenstein said the denser smoke could spread as far south as Washington, D.C., by midday Thursday.

Fine particle pollution from wildfire smoke can cause shortness of breath, coughing, dizziness or fatigue, and exacerbate heart and lung disease and other chronic health problems. Experts suggest reducing or eliminating outdoor activities, wearing an N95 mask if you have to be outside and keeping indoor air clean by closing windows and running an air purifier or air conditioner. In the long term, exposure to fine particulate matter from wildfire smoke is one of the leading causes of premature death.