Prolonged Chill Tightens Hold on the Great White North as US Records Hottest Christmas on Record.
An intense cold spell has seized a bitter and extended period of frigid weather, with readings persisting in the minus 20 to minus 40 Celsius range for an extended duration. A reading of -55.7 Celsius was logged in Braeburn, Yukon, on Tuesday, representing its most frigid December day in nearly five decades.
Enduring Chill Below -40C
Meanwhile, Mayo and Dawson endured over two straight weeks of nights colder than minus 40 degrees, with Mayo experiencing a low of -50.4C earlier this week. The capital, Whitehorse, likewise saw ten separate nights when the cold dipped under -30 Celsius.
The deep freeze spread farther south over the festive period. Christmas night saw Edmonton's temperatures plummet below minus 28C.
Boxing Day was expected to bring minimum temperatures of at least minus 20C in numerous areas, including Edmonton, Montreal, Ottawa and Quebec.
Forecast to Persist into the New Year
The frigid conditions are predicted to linger through the start of January. Officials have warned that the Yukon could face electricity outages over the next several days, as its energy infrastructure faces unprecedented demand from record-high energy demand.
The prolonged chill has been caused by the polar vortex remaining anchored above Canadian territory through December, enabling a surge of icy Arctic winds to descend. Next week, the cold air mass is expected to retreat north allowing more temperate air from the Pacific to sweep across the US and into parts of southern Canada.
Dramatic Difference 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.
Several states set Christmas Day temperature records. In Oklahoma, Oklahoma City hit 25C on Tuesday, exceeding the old record of 22C from 1982. Urban centers like Austin, Dallas, and Charlotte, North Carolina also logged readings above 25 degrees Celsius.
Heat-Dome Effect Drives the Heat
Unseasonable heat is predicted to persist on December 26th and into the weekend, with unseasonable heat forecast to sweep across the southeastern US in the coming days.
The unseasonable temperatures are powered by a powerful high-altitude ridge reaching from the arid southwest across the continent, establishing a classic heat-dome pattern. Such a configuration results in a widespread high-pressure system across much of the continent, trapping warm air near the surface. Sinking atmospheric air undergoes compression and additional heating, allowing unusually warm temperatures to build.
