Central Canada is getting hit with a blast of bitterly cold air, prompting Environment Canada to issue extreme cold warnings for much of Ontario and Quebec as winters sets in ahead of schedule.

The first official day of winter is Dec. 21, but wind chills in the forecast could make temperatures feel as low as -41 C in parts of both provinces over the next few days.

Some unseasonably cold air has also moved into southern British Columbia, with temperatures in Vancouver expected to be below freezing until Sunday. Arctic weather warnings have been issued as far south as the Fraser Valley, with wind chills there expected to make it feel like -20 C overnight.

David Phillips, senior climatologist for Environment Canada, says the cold that has been “gripping” Western Canada in recent days is now moving eastward.

“In the east, it looks like winter, but now it’s going to feel like winter,” Phillips told CTV News Channel on Wednesday.

He added that residents from coast to coast will see “temperatures that are clearly much colder for this time of the year, as we are a week away from the official beginning of winter.”

Phillips said Victoria and Vancouver will see temperatures, “they haven’t seen in four years,” while the Prairies can expect to feel 12-16 degrees colder than usual for this time of year.

On Wednesday and Thursday, temperatures in Ontario and Quebec will be six to eight degrees colder than normal for this time of year. Residents will get brief respite over the weekend when a “little bit of mild air” moves in, but it’ll be short-lived, says Phillips, as the cold air moves in again.

“The really good news is that, a week from now, we’re going to see a moderation of temperatures,” Phillips said. “Not above freezing, but certainly, much more civil, actually even a little milder in the west and near normal in the east.

“I think a lot of Canadians will feel that’s almost a festive gift from nature for what has been a very cold couple of weeks,” Phillips said.

Return of the polar vortex?

An Arctic air mass known as a polar vortex that could be making its return to Canada a little early this year, may already be causing temperatures to dip.

“The polar vortex kind of sits over us and just stays the course,” said Phillips. “It’s sort of like molasses. It’s thick and heavy, it hugs the ground, fills all the cracks and it just stays there, it takes a lot of energy to kick it out.”

At this time of the year, the polar vortex doesn’t last as long as it would in the dead of winter, Phillips said. But clearly, in the west, it’s been hanging around there like an unwanted house guest.”

No matter. By January, when Canadians see more of the polar vortex “we’ll be veterans of these weather wars,” Phillips said.