The smoke is also reaching North and South Dakota, according to The Associated Press.
“The drought conditions that we're seeing and the fire behaviour that we're seeing is something we haven't seen, as I said, in about 30 years,” Bill Mawdsley, who’s in charge of forest management for the N.W.T. Department of Environment and Natural Resources, told the CBC on Tuesday.
Highway 1 — Yellowknife’s primary road connection to the rest of the country — re-opened around 9 a.m. Wednesday morning after being closed due to smoke from fires burning between the small communities of Enterprise and Kakisa.
The situation remains extreme in the regions north and south of Great Slave Lake.
Environment Canada has issued a special air quality statement for all of Saskatchewan, as well as several communities in the N.W.T, including Yellowknife, Dettah, Fort Resolution, Fort Smith, Gameti, Whati, Behchoko and Lutsel K'e.
"Children, the elderly and those with respiratory problems should take care," it reads. "People in good health should consider reducing strenuous activities outdoors."
Rain in some parts of the region around Great Slave Lake is expected to quell some of the smoke Wednesday.
In Saskatchewan, the smoke is expected to move east and become less dense throughout the day.
Officials in the N.W.T. are also keeping a close eye on fires near Wekweeti, Gameti and Fort Reliance.
People in Kakisa, which has a population of 50, had to leave the community for a week as a fire raged around and through the town. They began returning home on the weekend.
The territorial parks at Reid Lake and Lady Evelyn Falls remain closed, and fire bans are in effect in all territorial parks in the North Slave, South Slave and Dehcho Regions.
Fires this summer have forced the territory's power corporation to temporarily close a hydroelectric dam. At one point, fires threatened crucial infrastructure that brings internet and cellular service to Yellowknife.
Last week, a fire destroyed a homestead on a remote part of Great Slave Lake, the life's work of two people who first settled in the area 27 years ago.