Prolonged Chill Grips Canada as United States Experiences Most Unseasonably Mild Christmas on Record.
An intense cold spell has seized a bitter and extended period of frigid weather, with temperatures hovering from 20 to 40 degrees below zero for multiple weeks. A reading of -55.7 Celsius was logged in Braeburn, Yukon, on Tuesday, its coldest December temperature in half a century.
Enduring Chill Below -40C
Similarly, the communities of Mayo and Dawson experienced 16 consecutive nights below -40C, with Mayo plunging to -50.4C earlier this week. The capital, Whitehorse, likewise saw ten separate nights when readings fell to minus 30 degrees or lower.
The bitter chill extended its reach south through Christmas week. On Christmas Day, overnight temperatures in Edmonton fell below -28C.
December 26th was anticipated to usher in readings no higher than -20 Celsius through a wide swath, including Edmonton, Montreal, Ottawa and Quebec.
Likely to Linger For Days to Come
This harsh winter weather is expected to continue through the start of January. Authorities have cautioned about potential power failures in the Yukon soon, as its energy infrastructure faces unprecedented demand from historically high electricity consumption.
This extended freeze is the result of a stationary polar vortex above Canadian territory through December, allowing bitter Arctic air to spill south. In the coming week, forecasts indicate this cold air will pull back northward slowly, permitting warmer Pacific winds to flow over the US and into parts of southern Canada.
Stark Contrast Compared to Stateside Temperatures
In stark contrast, parts of the US experienced the hottest December 25th in their history as temperatures soared about 15-30C above the seasonal average. Across wide regions, the atmosphere was more akin to late spring rather than the end of December.
Multiple states established new Christmas temperature highs. In Oklahoma, Oklahoma City hit 25C on Tuesday, topping the prior high mark of 22 degrees established over forty years ago. Urban centers like Austin, Dallas, and Charlotte, North Carolina were also among those that recorded temperatures above 25C.
High-Pressure System Fuels Warmth
Above-average warmth is expected to continue for the remainder of the week and beyond, with unseasonable heat forecast to sweep through the American Southeast soon.
This heat is being driven by a powerful high-altitude ridge extending from the desert south-west towards the north and east, establishing a classic heat-dome pattern. This setup creates an extensive zone of high atmospheric pressure across much of the continent, trapping warm air near the surface. As air sinks through the atmosphere, it compresses and heats further, allowing unusually warm temperatures to build.
