Prolonged Chill Envelops Canada as America Sees Warmest Christmas in History.

A prolonged deep freeze has enveloped a severe and lengthy Arctic outbreak, with readings persisting between -20C and -40C for an extended duration. On Tuesday, Braeburn in the Yukon recorded -55.7C, representing its most frigid December day since 1975.

Enduring Chill Below -40C

Similarly, the communities of Mayo and Dawson experienced 16 consecutive nights colder than minus 40 degrees, with Mayo plunging to -50.4C on Monday. Whitehorse also recorded ten separate nights when temperatures dropped below -30C.

The bitter chill extended its reach south through Christmas week. Christmas night saw Edmonton's temperatures plummet below minus 28C.

The day after Christmas was forecast to deliver minimum temperatures of at least minus 20C through a wide swath, including Edmonton, Montreal, Ottawa and Quebec.

Expected to Continue For Days to Come

The frigid conditions are predicted to linger through the start of January. Authorities have cautioned about potential power failures in the Yukon soon, as the territory’s power grid comes under strain from historically high electricity consumption.

This extended freeze is the result of a stationary polar vortex over Canada for much of December, allowing bitter Arctic air to spill south. In the coming week, forecasts indicate this cold air will pull back northward slowly, permitting warmer Pacific winds to flow over the US and into parts of southern Canada.

Pronounced Disparity Compared to Stateside Temperatures

Meanwhile, in a dramatic contrast, areas of the United States saw 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 instead of the heart of winter.

Several states set Christmas Day temperature records. The capital of Oklahoma soared to 25C on Christmas Day, surpassing the previous peak of 22C set in 1982. Cities including Austin and Dallas, in Texas, and Charlotte, North Carolina also logged readings above 25 degrees Celsius.

High-Pressure System Fuels Warmth

Unseasonable heat is predicted to persist for the remainder of the week and beyond, with atypical high temperatures expected to spread across the southeastern US in the coming days.

The warmth has been fuelled by a powerful high-altitude ridge extending from the desert south-west towards the north and east, which generates a heat-dome phenomenon. 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, enabling abnormally high temperatures to develop.