The smoke plumes that created dangerous air conditions throughout Minnesota on Monday have moved on, but wildfires still burning in Canada could lead to more air quality concerns this summer.

U.S. Forest Service: Active fire maps

Air quality in most of the state is now rated as "good," according to the Minnesota Pollution Control Agency.

A day after the agency issued a health alert for air quality across the state, the MPCA's air quality map showed smoke from Canadian wildfires had largely cleared away. This is a snapshot from the 6 a.m. air quality map Tuesday morning. Minnesota Pollution Control Agency

The smoke plumes have moved south and east out of Minnesota, said National Weather Service meteorologist Andy Lahr.

Smoke is still affecting air quality in the Dakotas and Canada, but Lahr said it's difficult to predict exactly where the smoke from the fires will head more than a couple days in advance.

"When the general upper air wind direction shifts a little bit, it can take the smoke plume and move it either away or back toward us," Lahr said. "So we could be dealing with this off and on later in the summer."

Even if smoke plumes again move into the state, Lahr said it's unlikely, although not impossible, that air quality will drop so low again. "That's about as bad as it gets down here," he said.

Monday's air quality levels were among the lowest ever measured in Minnesota, said Frank Kohlasch, manager of air assessment for the agency.

This National Weather Service map shows the trail of smoke from Canadian wildfires this morning. The smoke made for poor air quality across Minnesota on July 6. National Weather Service

Kohlasch said the very small particulates in the smoke can be especially dangerous to people with breathing or heart conditions, although otherwise healthy people can also be threatened by air quality levels like Monday's.

"They'll be breathed in, they'll get into the lungs, and some can even pass from the lungs into the bloodstream and then they can have effects on the heart," Kohlasch said. "These levels could bring on feelings of not feeling well or could exacerbate and could cause a pre-existing condition to get worse or to flare up."

Minnesota Pollution Control Agency: Air quality index

Pat Ericson, a resident of St. Paul's Como Park neighborhood, said Monday that she started to feel the effects of the smoke over the weekend.

This is the chart of the change in air quality this morning, after a day of smoky haze from Canadian wildfires across Minnesota. Minnesota Pollution Control Agency

"I'd been working in my gardens, and by early evening, we were having guests for dinner, and I started coughing," she said. "The next day I started hearing reports about air quality — I thought I was getting a cold."