The Canadian province of Quebec says rain and outside help could help win the fight against more than 100 forest fires producing plumes of smoke that have left cities on the Atlantic seaboard gasping for breath.
Officials say that by Monday there will be around 1,200 fire fighters, including more than 100 from France, battling blazes across a heavily wooded province of just 8.5 million people that covers more territory than Germany, Spain and France combined.
"Some rain is forecast ... in the next few days there is a risk the situation will stay critical. But the arrival of French firefighters is really going to help," forestry minister Maite Blanchette Vezina told reporters on Friday.
By late Friday there were 422 fires across Canada, 125 of them in Quebec. Canadian forest fires regularly occur in the warmer summer months but the scope of the current conflagration - and its early arrival - is unprecedented.
Federal meteorologist Gerald Cheng told reporters on Friday that some precipitation was expected over the weekend in Quebec, but added "whether or not that rain ... is enough to douse the fires, that remains to be seen".
Authorities in the Pacific province of British Columbia, where several small settlements have been evacuated, have made little mention of progress in the fight against blazes there.
"Right now conditions are very dry. Please use caution so that we can try our best to avoid a catastrophic fire season," British Columbia Premier David Eby told reporters on Friday.
More than 13,000 people have been evacuated from towns in the north of Quebec.
Vezina said some roads that had been closed were now open again, adding, "we're moving in the right direction." Asked about the potential for allowing people to actually return home, Quebec public safety minister Francois Bonnardel said, "It's clear that it (the situation) could stay problematic until Monday night".
The federal environment ministry is due to brief reporters at 11:30 a.m. EDT (1530 GMT) on Saturday to discuss the latest forecasts for Quebec and neighbouring Ontario.