MINNEAPOLIS (WCCO) — The Minnesota Pollution Control Agency has issued an air quality alert for nearly all of Minnesota, including the Twin Cities.

The alert goes into effect Wednesday at 10 p.m. and is expected to expire Friday at 3 p.m. Only a few counties bordering the North Shore of Lake Superior are not included in the alert.

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The MPCA said the alert was triggered by incoming smoke from Canadian wildfires, which will make its way to Minnesota via northerly winds.

(credit: MPCA)

“Heavy smoke is expected to arrive around 10 p.m. Wednesday near the Canadian border and mid-morning on Thursday in central and southern Minnesota. Smoke will remain over the area into Friday,” the agency reported Wednesday. “During this time, fine particle levels are expected to be in the Orange AQI category, a level that is considered unhealthy for sensitive groups. Fine particle levels will begin to improve Friday morning as southerly winds start moving the smoke out of the state.”

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Fine particle levels in northern Minnesota are considered very unhealthy for everyone.

MPCA says the air quality should improve by Friday afternoon.

The agency encourages people who are affected by unhealthy air quality, such as the elderly or those with respiratory or heart conditions, to limit their physical activity and take the proper precautions.

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The MPCA also urged Minnesotans to reduce their vehicle trips, use public transit, avoid backyard fires, and postpone use of gas-powered lawn equipment.