Deep Freeze Envelops Canada as America Sees Most Unseasonably Mild Christmas Ever.
An intense cold spell has seized an intense and prolonged cold spell, with thermometers lingering between -20C and -40C for an extended duration. On Tuesday, Braeburn in the Yukon recorded -55.7C, marking its chilliest December reading since 1975.
Enduring Chill in the Deep Minus Forties
In addition, the locales of Mayo and Dawson suffered through 16 consecutive nights colder than minus 40 degrees, with Mayo plunging to -50.4C earlier this week. Whitehorse also recorded a series of ten nights when temperatures dropped below -30C.
The deep freeze spread farther south through Christmas week. Christmas night saw Edmonton's temperatures plummet below minus 28C.
December 26th was anticipated to usher in minimum temperatures of at least minus 20C through a wide swath, encompassing cities from Edmonton to Quebec.
Forecast to Persist For Days to Come
The severe cold is forecast to persist through the start of January. 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.
This extended freeze is the result of the Arctic vortex settling across the northern part of the continent this month, 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 America and reach into portions of southern Canada.
Pronounced Disparity 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. In many areas, conditions felt more typical of 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. Urban centers like Austin, Dallas, and Charlotte, North Carolina were also among those that recorded temperatures above 25C.
Heat-Dome Effect Drives the Heat
Unseasonable heat is predicted to persist for the remainder of the week and beyond, with abnormal warmth projected to move through the American Southeast soon.
The warmth has been fuelled by a powerful high-altitude ridge extending from the desert south-west towards the north and east, creating a heat-dome effect. This setup creates an extensive zone of high atmospheric pressure over a large portion of North America, trapping warm air near the surface. Descending air compresses and adiabatically warms, fostering the buildup of exceptional warmth.
