Deep Freeze Tightens Hold on the Great White North as America Sees Hottest Christmas Ever.
A prolonged deep freeze has enveloped an intense and prolonged cold spell, with temperatures hovering between -20C and -40C for multiple weeks. A reading of -55.7 Celsius was logged in Braeburn, Yukon, on Tuesday, representing its most frigid December day in half a century.
Enduring Chill in the Deep Minus Forties
In addition, the locales of Mayo and Dawson suffered through 16 consecutive nights below -40C, with Mayo experiencing a low of -50.4C earlier this week. The capital, Whitehorse, likewise saw 10 nights when readings fell to minus 30 degrees or lower.
The deep freeze spread farther south over the festive period. Christmas night saw Edmonton's temperatures plummet below minus 28C.
The day after Christmas was forecast to deliver lows of at least -20C in numerous areas, from Edmonton in the west to Quebec in the east.
Likely to Linger For Days to Come
The frigid conditions are predicted to linger into the new year. Officials have warned that the Yukon could face electricity outages soon, as the system endures record-high pressure from record-high energy demand.
The lengthy cold snap originates from the Arctic vortex settling 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 allowing more temperate air from the Pacific to sweep across the United States and penetrate southern Canadian regions.
Pronounced Disparity with US Warmth
In stark contrast, parts of the US experienced historically high temperatures for Christmas as temperatures soared about 15-30C above the seasonal average. In many areas, conditions felt more typical of April or May rather than the end of December.
A number of states broke historical records for December 25th warmth. In Oklahoma, Oklahoma City hit 25C on Tuesday, surpassing the previous peak of 22C set in 1982. Urban centers like Austin, Dallas, and Charlotte, North Carolina were also among those that recorded temperatures above 25C.
Atmospheric Ridge Drives the Heat
Warmer-than-normal conditions are forecast to last through Boxing Day and the days ahead, with atypical high temperatures expected to spread through the American Southeast soon.
The unseasonable temperatures are powered by a strong upper-level ridge stretching from the southwestern deserts northward and eastward, creating a heat-dome effect. This pattern establishes a broad area of high pressure over a large portion of North America, which holds warm air close to the ground. Sinking atmospheric air undergoes compression and additional heating, fostering the buildup of exceptional warmth.
