Prolonged Chill Envelops Canada as United States Experiences Hottest Christmas in History.
A prolonged deep freeze has enveloped an intense and prolonged cold spell, with thermometers lingering from 20 to 40 degrees below zero for weeks. On Tuesday, Braeburn in the Yukon recorded -55.7C, representing its most frigid December day in half a century.
Prolonged Freeze Below -40C
Similarly, the communities of Mayo and Dawson experienced sixteen nights in a row colder than minus 40 degrees, with the temperature in Mayo bottoming out at -50.4 degrees Celsius at the start of the week. Whitehorse similarly reported 10 nights when the cold dipped under -30 Celsius.
The deep freeze spread farther south over the festive period. Christmas night saw Edmonton's temperatures plummet below minus 28C.
Boxing Day was expected to bring lows of at least -20C in numerous areas, from Edmonton in the west to Quebec in the east.
Expected to Continue For Days to Come
This harsh winter weather is expected to continue through the start of January. There are warnings of possible electrical grid strain in Yukon territory soon, as its energy infrastructure faces unprecedented demand from peak power usage levels.
This extended freeze is the result of the polar vortex remaining anchored above Canadian territory through December, allowing bitter Arctic air to spill south. The frigid dome is projected to gradually withdraw north gradually, enabling milder Pacific air to move across the United States and penetrate southern Canadian regions.
Stark Contrast with US Warmth
Meanwhile, in a dramatic contrast, areas of the United States saw the hottest December 25th in their history as temperatures soared about 15-30C above the seasonal average. For numerous locations, the weather resembled a spring day in 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, topping the prior high mark of 22 degrees established over forty years ago. Metropolitan areas such as Austin, Dallas, and Charlotte also logged readings above 25 degrees Celsius.
High-Pressure System Fuels Warmth
Above-average warmth is expected to continue 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 robust atmospheric ridge reaching from the arid southwest across the continent, establishing a classic heat-dome pattern. This setup creates an extensive zone of high atmospheric pressure across much of the continent, effectively capping warm air at lower altitudes. Descending air compresses and adiabatically warms, allowing unusually warm temperatures to build.
