‘Keep Windows Closed’ 60+ MN Counties Told As Canadian Smoke Ruins Perfect Weather Week

MINNEAPOLIS–ST. PAUL, MN — It’s sunny, dry, and pleasantly warm, the kind of summer weather Minnesotans wait for all year.

But health officials are once again urging residents to stay inside and "keep windows closed overnight to prevent smoke from getting indoors," as thick wildfire smoke from Canada continues to blanket the state.

The Minnesota Pollution Control Agency has issued a statewide Air Quality Alert through 5 p.m. Saturday, warning that fine particle pollution (PM2.5) has reached unhealthy levels across the Twin Cities metro and much of the state.

The alert includes more than 60 counties, covering cities like Minneapolis, St. Paul, Duluth, Rochester, Mankato, and St. Cloud, along with Tribal Nations such as Mille Lacs, Prairie Island, and Upper Sioux.

What’s Causing the Bad Air?

Wildfire smoke from Manitoba and Saskatchewan is being funneled into Minnesota by persistent northerly winds. A dome of high pressure is parked over the region, leading to calm conditions and poor air dispersion, meaning the smoke is staying trapped near the surface.

The smoke is expected to linger through at least Saturday afternoon, when winds may finally shift and help clear the air.

Twin Cities Air Quality Forecast

• Wednesday, July 30: AQI 158 — Unhealthy for all
• Thursday, July 31: Unhealthy for all
• Friday, Aug. 1: Unhealthy for sensitive groups

Even short-term exposure to unhealthy levels of fine particles can cause respiratory irritation and worsen conditions such as asthma and heart disease. When the AQI hits the red zone, everyone is advised to limit prolonged or heavy exertion outdoors.

Frustrating Timing: The Weather Is Nearly Perfect

Here’s the National Weather Service forecast for the Twin Cities:

• Wednesday: Partly sunny, high near 79. Areas of smoke through 11 a.m.
• Thursday: Mostly sunny, high near 77.
• Friday: Sunny, high near 78.
• Saturday: Mostly sunny, high near 78.
• Sunday: Partly sunny, high near 74, slight chance of showers.
• Monday–Tuesday: Partly sunny, highs in the mid-70s to low 80s, with a continued slight chance of storms.

It’s the classic summer paradox: beautiful days, but not safe to enjoy them outside.

Health Advice

According to the MPCA and the National Weather Service:

• Everyone should limit long or intense outdoor activity when the AQI reaches unhealthy levels.
• Sensitive groups, including people with lung or heart conditions, older adults, children, and anyone active outdoors, should avoid outdoor exertion entirely.
• Windows should remain closed overnight to prevent smoke from getting indoors.
• Reduce activities that add to air pollution, such as outdoor burning, using wood stoves, and unnecessary driving.