Deep Freeze Envelops the Great White North as America Sees Hottest Christmas in History.
A prolonged deep freeze has enveloped an intense and prolonged cold spell, with readings persisting in the minus 20 to minus 40 Celsius range for multiple weeks. This week, the Yukon community of Braeburn saw the mercury drop to -55.7C, its coldest December temperature since 1975.
Prolonged Freeze in the Deep Minus Forties
In addition, the locales of Mayo and Dawson suffered through sixteen nights in a row below -40C, with Mayo plunging to -50.4C earlier this week. The capital, Whitehorse, likewise saw ten separate nights when temperatures dropped below -30C.
This Arctic air mass pushed further southward over the festive period. On Christmas Day, overnight temperatures in Edmonton fell below -28C.
Boxing Day was expected to bring readings no higher than -20 Celsius across many regions, encompassing cities from Edmonton to Quebec.
Forecast to Persist For Days to Come
The frigid conditions are predicted to linger for the foreseeable future. There are warnings of possible electrical grid strain in Yukon territory in the coming days, as the territory’s power grid comes under strain from peak power usage levels.
The prolonged chill has been caused by the Arctic vortex settling above Canadian territory through December, enabling a surge of icy Arctic winds to descend. In the coming week, forecasts indicate this cold air will pull back northward allowing more temperate air from the Pacific to sweep across America and reach into portions of southern Canada.
Dramatic Difference to American Heat
In stark contrast, parts of the US experienced historically high temperatures for Christmas as temperatures soared about 15-30C above the seasonal average. For numerous locations, the weather resembled a spring day in April or May than late December.
Several states set Christmas Day temperature records. The capital of Oklahoma soared to 25C on Christmas Day, exceeding the old record of 22C from 1982. Metropolitan areas such as Austin, Dallas, and Charlotte similarly saw thermometers rise past the 25C mark.
Heat-Dome Effect Drives the Heat
Unseasonable heat is predicted to persist through Boxing Day and the days ahead, with unseasonable heat forecast to sweep through the American Southeast soon.
The unseasonable temperatures are powered by a strong upper-level ridge reaching from the arid southwest across the continent, creating a heat-dome effect. Such a configuration results in a widespread high-pressure system over a large portion of North America, effectively capping warm air at lower altitudes. Sinking atmospheric air undergoes compression and additional heating, fostering the buildup of exceptional warmth.
