Canadians from the Prairies to Atlantic Canada are in the grip of an Arctic air mass that has brought frigid temperatures and harsh winds to a massive swath of the country.

"It's a cold one," said CTV weather specialist Jeff Hutcheson. "It's even colder than yesterday and the cold has spread now into Atlantic Canada, including Newfoundland and Labrador, in terms of having wind-chill warnings there."

In Saskatchewan, Manitoba, northern Ontario and much of Quebec, residents were warned by Environment Canada that wind-chill will drag down temperatures down to between -40 and -50 C.

In Toronto, the temperature felt like -24 on Thursday morning.

Even into Atlantic Canada, residents were bundling up as the mercury hovered between -20 and the mid minus thirties, with wind-chill factored in.

Temperatures drop in P.E.I.

Prince Edward Island, where temperatures were hovering around zero degrees as recently as Wednesday, saw a steep drop on Thursday. Environment Canada warned Islanders that the wind chill would make temperatures feel as cold as -38 by the evening and into Friday morning.

Here is a selection of Canadian cities, and their temperatures with the wind chill Thursday evening:

• Regina: - 29
• Winnipeg: - 40
• Thunder Bay, Ont.: -34
• Ottawa.: --29
• Toronto.: -22
• Montreal: -27
• Fredericton, N.B.: -25
• Charlottetown: -27
• Sydney, N.S.: -24
• Corner Brook, N.L.: -25

"You've got again a situation where wind chills are exceptionally dangerous this morning and this afternoon," Hutcheson said.

Risk to exposed skin

He warned that exposed skin can freeze in minutes under such deep-cold conditions.

When temperatures are between -28 and -39, exposed skin can freeze between 10 and 30 minutes, Hutcheson said.

When the mercury is between -40 and -47, it only takes five to 10 minutes.

Between -48 and -54, it only takes two to five minutes for skin to freeze, he said.

Calgary residents were enjoying a virtual tropical holiday, when compared with much of the rest of the country.

Environment Canada's forecast for the city predicted a low of three degrees, and a high of 10 degrees, with similar temperatures lasting through the weekend.

The anomaly also affected Vancouver, where temperatures were expected to reach six degrees, and Victoria, at nine degrees, and even Whitehorse, Yukon, where the temperature was four degrees.