Overnight rain helped firefighters stall a large wildfire near the Canadian oil sands city of Fort McMurray, Alberta, and wet weather on Thursday was expected to further aid containment efforts, local officials said.

The region received rain for a few hours through the night, and the forecast for the next few days is for more precipitation, officials for the Regional Municipality of Wood Buffalo, which includes Fort McMurray, said at a briefing.

"This type of weather provides a good window for firefighters to make progress," wildfire information officer Josee St-Onge said.

The fire stayed about 5.5 km (3.4 miles) from the landfill on the city's southern outskirts, where crews are building a containment line.

It is the only one out of 44 wildfires burning in Alberta deemed out of control, and St-Onge warned against complacency due to the rain, saying more work was needed to contain the blaze.

Fort McMurray is the hub for most of Canada's oil output. A huge wildfire in 2016 forced the evacuation of 90,000 residents, burned down 2,400 buildings and idled more than 1 million barrels per day (bpd) of production.

A smaller, separate wildfire that had ignited to the city's north was also being held and not creeping closer, officials said.

There have been no reports of fire-related disruption to Alberta oil and gas production, though research firm Rystad Energy estimated that more than 2.1 million bpd of marketable oil sands output – or 2.6 percent of total crude oil and lease condensate supply – could be at risk if conditions materially worsen.