The unseasonably warm weather affecting much of Canada this winter has forced Ontario's largest ski hill to lay off 1,300 staff.

Blue Mountain issued layoff notices Friday to its part-time and seasonal staff, including front-desk employees, marketing staff and lift operators.

About 400 core workers will remain on the job maintaining the hotel and other services.

"It was a tough decision to make, and we didn't make it lightly," Paul Pinchbeck, Blue Mountain's director of marketing, told CBC News Friday. "It's unfortunately become a step we just absolutely had to take."

Even with state-of-the-art snow-making equipment, the humidity and rain have hampered snow-making efforts and made it impossible to keep more than one or two runs open this winter, Pinchbeck said.

"It's been extraordinarily difficult because even though we've had some negative temperatures at night, they've come in short windows," he said.

The layoff notices are for three weeks, but Pinchbeck said he hopes they could have some ski operations open as early as Wednesday, based on next week's forecast. That could mean the hill could be back to full operation two weeks after that.

The layoffs come as more bad news for the nearby town of Collingwood, which is reelingfrom the loss of 330 jobs atits Alcoa aluminum plant.

"We know the people that are directly affected by layoffs and job closures and it affects them on a personal level and we're concerned for those families and those people facing unemployment," said Chris Carrier, Collingwood's mayor.

Carrier said the shutdown would result in a loss of traffic through the town to the resort and affect shops and businesses in the area.