The latest: Try not to breathe the outdoor air, National Weather Service says

Smoke from a raging Canadian wildfire is expected to drift over Minnesota and Wisconsin by Thursday morning, the National Weather Service says.

However, most of the smoke is expected to remain relatively high in the atmosphere, about 15,000 feet, so significant air quality concerns are not expected.

But hazy conditions are expected, and people who are highly sensitive to air pollution are advised to monitor conditions. The Minnesota Pollution Control Agency posts air quality information on its website at www.pca.state.mn.us.

The Canadian wildfire has forced the evacuation of Fort McMurray, Alberta, where officials warned Wednesday that all efforts to suppress the fire have failed.

About 88,000 residents successfully evacuated as flames moved into the city surrounded by wilderness in the heart of Canada’s oil sands. No injuries have been reported but the fire had destroyed or damaged an estimated 1,600 structures by Wednesday.

Unseasonably hot temperatures combined with dry conditions have transformed the boreal forest in much of Alberta into a tinder box.