Canadian winter living up to its reputation as Arctic air chills Eastern provinces

Central and Eastern Canada have been plunged into the depths of winter this week, as a cold snap stretching from eastern Alberta to Atlantic Canada was in full swing Tuesday and Wednesday, in some cases straining power grids.

An outage cut power to nearly 100,000 Montreal addresses early Tuesday as temperatures dropped to -15 C, leaving more than 15,000 without power at one point. Early Wednesday morning, Hydro-Québec reported separate outages at more than 3,700 locations in Montreal, while parts of northern Quebec were under a blizzard warning late Wednesday.

Around 4,900 lost power in and around the New Brunswick city of Edmundston Tuesday morning, as Environment Canada reported temperatures dropping to -32 C.

In Toronto, temperatures dipped to -18 C early Wednesday morning, before climbing to -11 C by 7 p.m. — compared to an average high of -2 C this time of year, according to Environment and Climate Change Canada (ECCC) meteorologist Brad Rousseau.  

"Things are pretty much on track as we expected. The cold air is firmly entrenched," he said.

Toronto had opened several warming centres and dispatched additional homelessness outreach workers in preparation for the cold snap.

Parts of Northern Ontario remained under extreme cold warnings late Wednesday, with wind chill temperatures expected to hit -40 C.

In Nova Scotia, Halifax Water warned customers to be aware of their internal plumbing to prevent frozen pipes Tuesday as temperatures dipped to -16 C.

Much of Manitoba was under extreme cold warnings over the weekend. While the warnings were no longer in place Wednesday, Winnipeg temperatures were expected to drop to -28 C overnight, but with a forecast high of -2 C by Friday.

Reprieve expected by the weekend

Rousseau said the colder air is expected to relax a bit into the weekend, but will come back next week, although temperatures are expected to be less severe.

He said while the cold spell has not broken any temperature records, it may feel especially extreme because these cold stretches have been fewer and further between in recent years. 

Last year's winter was 5.2 C above the baseline average according to ECCC data, making it the warmest on nationwide records dating back to 1948, and 1.1 C higher than the previous warmest winter, recorded in 2009-2010.

"It kind of makes it that much more dramatic, that it's been such a long period of time between these drastic cold spells," Rousseau said.

Late Wednesday afternoon, Cape Stallworthy, Nunavut was the coldest spot in Canada at -31.3 C.

Cold spells like this can be caused by a disruption in the polar vortex that swirls above the North and South Pole. The ring of cold air stretches out across North America, which can affect winds closer to the surface and allow Arctic air to spill out.  

WATCH | Is a polar vortex to blame for the cold weather?:

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A big outbreak of Arctic air is about to drop temperatures across North America. But is the ‘polar vortex’ to blame?

The cold spell has gone far below the border and wreaked havoc across the U.S., with winter storms battering the gulf coast in the southern states, after Monday's presidential inauguration and parade in Washington, D.C., were moved indoors due to cold weather.

"Basically, we get these strong, high-pressure systems that will develop north of the prairies, kind of in the territories over the Arctic, and as they descend south and eastward, they will bring down that arctic air with them," Rousseau said.

He said another Arctic high-pressure system is currently entrenched over Western Canada and will slowly drift east, bringing cold air back after a slight reprieve.

Environment Canada has warned the risk of conditions like windburn and frostbite increase whenever wind chill values drop below -27 C.

The agency said extreme cold puts everyone at risk, but young children, seniors, people with chronic illness, people working outdoors and people who are unhoused are particularly vulnerable. Families are also warned to keep pets indoors in extreme cold.