Air quality alerts are in effect for Minnesota, Michigan and Wisconsin, with the air quality index predicted to reach Level 3 — unhealthy for sensitive groups — or 4, unhealthy for all. These alerts mean people should avoid strenuous outdoor activities, especially those with heart disease and asthma, and keep windows closed to prevent smoke from getting indoors.

Places experiencing reduced air quality and/or visibility Friday include the areas around Duluth and Silver Bay in Minnesota; Houghton and Marquette in Michigan; and Wausau, Green Bay and Madison in Wisconsin.

Moderate smoke may reach as far south as Chicago, St. Louis and Detroit on Friday evening before blowing into the East on Saturday.

Wildfire smoke forecast

Winds blowing from north to south will transport smoke from Canada to the United States during the coming days.

On Friday, smoke spread from the northern Plains to the Midwest.

The highest concentrations of smoke had been expected near the Great Lakes, with 13 states — Montana, North Dakota, South Dakota, Nebraska, Kansas, Minnesota, Iowa, Missouri, Wisconsin, Illinois, Indiana, Michigan and Ohio — at some risk for smoky skies.

On Saturday, light to moderate smoke is forecast to extend from the Plains to the East Coast.

The heaviest smoke is expected in the Dakotas, Minnesota and Iowa.

Smoke may reach the Mid-Atlantic and Southeast during the late morning or afternoon, although it’s uncertain whether there will be enough smoke to significantly reduce air quality in these areas.

This time, the worst fires are farther away — about 1,500 miles away from D.C., in central Manitoba — meaning that a repeat of 2023 is unlikely for the Eastern Seaboard.

How long it will last

Smoke may continue to blow southward across central and eastern states Sunday, although changing winds early next week may bring a reprieve.

Some of the smoke is stretching as far east as Newfoundland, Canada, and could even reach the Azores, Ireland and Britain on Saturday, and perhaps Norway by early Sunday.