Deep Freeze Grips the Great White North as US Records Warmest Christmas on Record.

A prolonged deep freeze has enveloped a severe and lengthy Arctic outbreak, with thermometers lingering between -20C and -40C for an extended duration. 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 of Extreme Cold

In addition, the locales of Mayo and Dawson suffered through over two straight weeks of nights below -40C, with Mayo plunging to -50.4C at the start of the week. Whitehorse similarly reported 10 nights when the cold dipped under -30 Celsius.

This Arctic air mass pushed further southward through Christmas week. On Christmas Day, overnight temperatures in Edmonton fell below -28C.

December 26th was anticipated to usher in readings no higher than -20 Celsius through a wide swath, from Edmonton in the west to Quebec in the east.

Forecast to Persist For Days to Come

This harsh winter weather is expected to continue into the new year. There are warnings of possible electrical grid strain in Yukon territory soon, as the territory’s power grid comes under strain from record-high energy demand.

The prolonged chill has been caused by the Arctic vortex settling across the northern part of the continent this month, which funnels frigid northern air southward. Next week, the cold air mass is expected to retreat north gradually, enabling milder Pacific air to move across the US and into parts of southern Canada.

Pronounced Disparity to American Heat

Conversely, sections of America recorded 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 instead of the heart of winter.

Several states set Christmas Day temperature records. In Oklahoma, Oklahoma City hit 25C on Tuesday, exceeding the old record of 22C from 1982. Cities including Austin and Dallas, in Texas, and Charlotte, North Carolina were also among those that recorded temperatures above 25C.

Heat-Dome Effect Sustains High Temperatures

Unseasonable heat is predicted to persist for the remainder of the week and beyond, with unseasonable heat forecast to sweep through the American Southeast soon.

The warmth has been fuelled by a robust atmospheric ridge stretching from the southwestern deserts northward and eastward, establishing a classic heat-dome pattern. This setup creates an extensive zone of high atmospheric pressure over a large portion of North America, trapping warm air near the surface. As air sinks through the atmosphere, it compresses and heats further, enabling abnormally high temperatures to develop.