Canada's western provinces are under a deep freeze that has caused governments to issue travel advisories and put homeless people at risk in several cities.

In Calgary, passers-by found one man dead on the streets early Saturday. Insp. Steve Barlow of the Calgary police said a cause of death hasn't been determined, but the cold temperatures could be a factor.

The city of Calgary kept people warm in idling buses Saturday and turned the grandstand at Exhibiton and Stampede Park into a temporary shelter. The forecast for the city for the next few days is -20.

The city's shelters are overflowing and with a planned shelter stalled by appeals from area residents, the city is short on beds.

"In order to use the grandstand building, the city of Calgary had to determine that this was an emergency situation and required an immediate response," said city spokesman Chris Branch.

Housing is a premium in Calgary, which has experienced an economic boom that has attracted workers from all over Canada.

Gary Smith, one of hundreds of workers who have jobs in Calgary but have been unable to find housing, stayed at a drop-in centre Friday night, but it was full when he got off work at 4 p.m. on Saturday.

"Most of the people staying in shelters who don't have a home right now are workers who have come to Calgary to help work ... during the (construction) boom," Smith said.

Calgary firefighters struggled to stay warm as they fought a blaze Saturday afternoon that resulted in the evacuation of three adjacent apartment buildings.

In Edmonton, where temperatures hovered at -15 degrees Celsius on Saturday afternoon and fell to -22 by the evening, homeless people were doing what they could to stay warm on the weekend. Most Edmonton shelters are open from Monday through Friday.

"I go into malls, go onto transit, go anywhere that's warm," Gerry Lalonde, who doesn't have a home, told CTV Edmonton.

The Mustard Seed Church ministry in Edmonton has put out an appeal for clothing, blankets and gloves to help keep people warm.

"There's no other resource for some of them so it's important all the agencies work together and make sure people keep warm," said Mariam Leslie, the church's volunteer coordinator.

Elsewhere on the Prairiees, overnight lows in the -20 range are expected in Regina, with Saskatoon a bit colder. Winnipeg should be slightly milder, with overnight lows in the -15 range.

Meanwhile, Toronto was expected to stay above freezing overnight and experience a daytime high of +11 on Sunday. Temperatures in Atlantic Canada are also expected to be relatively mild on Sunday.

Vancouver's snow troubles

In Vancouver, the poor weather conditions forced a 14-passenger plane to make an emergency landing at the Tsawwassen ferry terminal on Saturday. No one was hurt.

Travellers were being warned to expect flight delays and cancellations at Vancouver International Airport on Sunday.

Environment Canada has forecast as many as 30 centimetres of snow for the Lower Mainland by Monday -- good news for ski hills and tire shops, but bad news for everyone else.

Air Canada said passengers should check on the status of their flights before heading to the airport.  

With a pre-Christmas cold snap on the way in Vancouver, where temperatures are more often moderate, social service agencies in Vancouver were on a quest for more shelter beds.

The Salvation Army on the city's Downtown Eastside, which has 237 beds, said it was gathering bedding in advance of an increased demand.

"We anticipate we're going to be full to overflowing,'' Capt. John Murray told The Canadian Press.

Sleeping mats have been spread on the floor in a large multi-purpose room and a dining area, he said.

Murray said the organization is grateful to the Buddhist Tzu Chi Foundation, which bought the Army and Navy department store's entire stock of blankets -- about 400 -- and donated them.

Snowfall elsewhere in B.C. resulted in the provincial government issuing travel advisories, warning drivers to be aware of snowy conditions in areas west of both Glacier and Yoho national parks in eastern B.C.

Snow in other parts of B.C. led the provincial government to warn drivers were warned to be aware of snowy conditions in the areas west of both Glacier and Yoho national parks in eastern B.C.

In the North Central Interior of B.C., temperatures are expected to be in the -25 range.

With reports from CTV's Kevin Green in Calgary and Nashiha Naqvi in Edmonton, and files from The Canadian Press