🔗 Share this article Arctic Blast Grips Canada as US Records Most Unseasonably Mild Christmas on Record. Northern Canada has been gripped by an intense and prolonged cold spell, with readings persisting from 20 to 40 degrees below zero for an extended duration. On Tuesday, Braeburn in the Yukon recorded -55.7C, its coldest December temperature in nearly five decades. Consecutive Nights of Extreme Cold Meanwhile, Mayo and Dawson endured 16 consecutive nights dipping under the minus 40 Celsius threshold, with Mayo experiencing a low of -50.4C on Monday. The capital, Whitehorse, likewise saw a series of ten nights when readings fell to minus 30 degrees or lower. The bitter chill extended its reach south over the festive period. Christmas night saw Edmonton's temperatures plummet below minus 28C. Boxing Day was expected to bring lows of at least -20C through a wide swath, from Edmonton in the west to Quebec in the east. Forecast to Persist into the New Year This harsh winter weather is expected to continue into the new year. There are warnings of possible electrical grid strain in Yukon territory in the coming days, as its energy infrastructure faces unprecedented demand from historically high electricity consumption. The lengthy cold snap originates from the polar vortex remaining anchored across the northern part of the continent this month, which funnels frigid northern air southward. The frigid dome is projected to gradually withdraw north allowing more temperate air from the Pacific to sweep across the United States and penetrate southern Canadian regions. Pronounced Disparity to American Heat Meanwhile, in a dramatic contrast, areas of the United States saw historically high temperatures for Christmas 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. The capital of Oklahoma soared to 25C on Christmas Day, topping the prior high mark of 22 degrees established over forty years ago. Urban centers like Austin, Dallas, and Charlotte, North Carolina similarly saw thermometers rise past the 25C mark. High-Pressure System Sustains High Temperatures Above-average warmth is expected to continue for the remainder of the week and beyond, with unseasonable heat forecast to sweep across the southeastern US in the coming days. The unseasonable temperatures are powered by a robust atmospheric ridge reaching from the arid southwest across the continent, which generates a heat-dome phenomenon. Such a configuration results in a widespread high-pressure system over a large portion of North America, which holds warm air close to the ground. Descending air compresses and adiabatically warms, enabling abnormally high temperatures to develop.