Canadian Wildfire Smoke Blankets Midwest, Settles In Major US Cities

ST. PAUL, MN. - JUNE 2023: Two boats go north on the Mississippi River as heavy smoke blankets downtown St. Paul, Minn., Wednesday June 14, 2023. Smoke from Canadian wildfires blowing into Minnesota has affected the Twin Cities and the rest of the state's air quality. The Minnesota Pollution Control Agency issued an air quality alert covering the northern half of the state, the metro area and a portion of southern Minnesota. (Photo by Jerry Holt/Star Tribune via Getty Images)

Canadian wildfire smoke is once again causing air quality to reach unhealthy levels in major cities in the United States, but unlike last week when the thickest smoke blew over the Northeast, the latest spell of smoke is settling across the Midwest.

Smoke started to pour over Minnesota, North Dakota and South Dakota earlier in the week, and by Thursday morning, wind had carried high-altitude smoke as far south as Oklahoma and as far east as Pennsylvania and New York City. The thickest smoke stretched from southern Minnesota to central Ohio.