Arctic air mass grips much of the country in bitterly cold temperatures

A deep freeze is descending on much of Canada, courtesy of an Arctic air mass. Environment Canada forecasts an extreme wind chill in Winnipeg will bring temperatures as low as -40 C.

Much of Canada is still in the grips of a deep arctic chill today, as temperatures from the Rockies to the Appalachians continue in the negative double-digits this morning and will likely stay there for the rest of the week.

The typical Canadian winter has certainly returned with a vengeance after being exiled by La Niña for the past two years. The current cold snap is due to the jet stream dipping far to the south and dragging an Arctic air mass along with it, plunging temperatures as far south as Texas well below freezing.

Southwestern British Columbia was the only part of the country this morning that managed to stay above freezing this morning, but that is probably little consolation, since they are still dealing with cold, rainy weather that is forecast to last at least through the weekend.

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In the prairie provinces, temperatures were warmest in Alberta, where they only got down to -13°C in Calgary and -14°C in Edmonton, but for Saskatchewan and Manitoba the mercury bottomed out between -25°C and -30°C, with wind chills making it feel more like -30 to -40 degrees!

In Ontario, temperatures got down to nearly -20°C near the lakes and Ottawa reached a frosty -28°C, with even the light winds blowing across the province making those temperatures feel at least 10 degrees colder! Eastern regions of the province are under a wind chill warning for this morning and likely again for tonight!

Wind chill warnings for Québec, New Brunswick, Prince Edward Island and the north shore of Nova Scotia as well, as temperatures hover between -15°C to -25°C this morning from Montréal to Amherst, NS — and even colder further north — with extreme wind chills expected for today and tonight.

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The rest of Nova Scotia, including Cape Breton Island, and the Island of Newfoundland are spared any extreme wind chills, but temperatures up and down the coast are still in the minus-teens this morning, with the Avalon Peninsula managing to stay just a bit warmer, but with this extreme chill creeping across the country, they may be in for it before the week is over.

Gradual warming is expected through the rest of the week, as this arctic airmass lumbers its way across the country, but with the jet stream dipping so far south this season (a good indicator of the negative phase of the Arctic Oscillation), we might be in for more of these deep freezes before the season is over. Bundle up!

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