Deep Freeze Grips Canada as United States Experiences Hottest Christmas in History.
Northern Canada has been gripped by a bitter and extended period of frigid weather, with temperatures hovering from 20 to 40 degrees below zero for weeks. This week, the Yukon community of Braeburn saw the mercury drop to -55.7C, its coldest December temperature in half a century.
Consecutive Nights of Extreme Cold
Similarly, the communities of Mayo and Dawson experienced over two straight weeks of nights below -40C, with Mayo experiencing a low of -50.4C at the start of the week. Whitehorse similarly reported a series of ten nights when temperatures dropped below -30C.
The bitter chill extended its reach south over the festive period. In Edmonton, the Christmas overnight low dipped under -28 degrees Celsius.
Boxing Day was expected to bring minimum temperatures of at least minus 20C across many regions, including Edmonton, Montreal, Ottawa and Quebec.
Forecast to Persist For Days to Come
The frigid conditions are predicted to linger for the foreseeable future. Officials have warned that the Yukon could face electricity outages in the coming days, as its energy infrastructure faces unprecedented demand from historically high electricity consumption.
The lengthy cold snap originates from a stationary polar vortex 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 America and reach into portions of southern Canada.
Dramatic Difference with US Warmth
Conversely, sections of America recorded the hottest December 25th in their history as the mercury climbed roughly 15 to 30 degrees above typical averages. In many areas, conditions felt more typical of April or May than late December.
A number of states broke historical records for December 25th warmth. Oklahoma City, Oklahoma, reached 25 degrees Celsius on Christmas, 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
Warmer-than-normal conditions are forecast to last on December 26th and into the weekend, with atypical high temperatures expected to spread 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 blanketing a significant part of the landmass, trapping warm air near the surface. As air sinks through the atmosphere, it compresses and heats further, fostering the buildup of exceptional warmth.
