MADISON, Wis. — Smoke from Canadian wildfires has prompted health warnings across the Upper Midwest and Montana for the second year in a row.
Fires raging in British Columbia and Alberta have filled the skies with haze over parts of Montana, the Dakotas, Minnesota and Wisconsin on Sunday, lingering into Monday morning.
Unhealthy air pollution levels mean everyone in Minnesota should stay indoors and avoid heavy exertion outdoors, the Minnesota Pollution Control Agency said in its first statewide air quality alert of the season Sunday. Scheduled to end at noon Monday, the advisory was extended until 11 p.m. for southern Minnesota including the Twin Cities metro area.
The Wisconsin Department of Natural Resources said the air quality was unhealthy for sensitive people in multiple counties across the state's northern two-thirds on Sunday. Set to end at noon Monday, the advisories were kept in place until midnight.
Michigan's Upper Peninsula was also under hazy skies Monday. Some people reported the smell of smoke, said Joe Phillips, a National Weather Service meteorologist in Marquette, Michigan.
Prevailing winds could send the smoke south and east as far as Iowa and Chicago, leaving skies looking milky by late Tuesday or early Wednesday, said Rafal Ogorek, a meteorologist in the National Weather Service's Chicago office. Most of the smoke was expected to linger over Minnesota, Wisconsin and northern Michigan, hanging between a mile (1.6 kilometers) and 2 miles (3 kilometers) above the ground.
A record number of wildfires in 2023 forced more than 235,000 people across Canada to evacuate and sent thick smoke into parts of the U.S., prompting hazy skies and health advisories in multiple U.S. cities.
There were 200 fires burning in Canada by mid-May last year, compared with 90 fires as of this Sunday, said Dave Phillips, senior climatologist at Environment and Climate Change Canada, a government environmental protection agency. A fire raging near Fort Nelson in British Columbia's far northeastern corner has forced evacuations.