Prolonged Chill Envelops Canada as United States Experiences Most Unseasonably Mild Christmas on Record.

A prolonged deep freeze has enveloped a bitter and extended period of frigid weather, with readings persisting between -20C and -40C for multiple weeks. This week, the Yukon community of Braeburn saw the mercury drop to -55.7C, marking its chilliest December reading in half a century.

Enduring Chill in the Deep Minus Forties

In addition, the locales of Mayo and Dawson suffered through 16 consecutive nights below -40C, with Mayo experiencing a low of -50.4C at the start of the week. The capital, Whitehorse, likewise saw 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 minimum temperatures of at least minus 20C across many regions, from Edmonton in the west to Quebec in the east.

Forecast to Persist into the New Year

The severe cold is forecast to persist into the new year. Officials have warned that the Yukon could face electricity outages in the coming days, as the territory’s power grid comes under strain from peak power usage levels.

The lengthy cold snap originates from the polar vortex remaining anchored across the northern part of the continent this month, enabling a surge of icy Arctic winds to descend. The frigid dome is projected to gradually withdraw north allowing more temperate air from the Pacific to sweep across the US and into parts of southern Canada.

Stark Contrast to American Heat

Conversely, sections of America recorded their warmest Christmas Day on record as temperatures soared about 15-30C above the seasonal average. In many areas, conditions felt more typical of April or May rather than the end of December.

Multiple states established new Christmas temperature highs. Oklahoma City, Oklahoma, reached 25 degrees Celsius on Christmas, surpassing the previous peak of 22C set in 1982. Metropolitan areas such as Austin, Dallas, and Charlotte also logged readings above 25 degrees Celsius.

High-Pressure System Drives the Heat

Unseasonable heat is predicted to persist through Boxing Day and the days ahead, with unseasonable heat forecast to sweep across the southeastern US in the coming days.

This heat is being driven by a robust atmospheric ridge reaching from the arid southwest across the continent, creating a heat-dome effect. This pattern establishes a broad area of high pressure across much of the continent, trapping warm air near the surface. As air sinks through the atmosphere, it compresses and heats further, enabling abnormally high temperatures to develop.