Deep Freeze Tightens Hold on the Great White North as US Records Hottest Christmas on Record.
A prolonged deep freeze has enveloped a severe and lengthy Arctic outbreak, with thermometers lingering from 20 to 40 degrees below zero for weeks. A reading of -55.7 Celsius was logged in Braeburn, Yukon, on Tuesday, marking its chilliest December reading in nearly five decades.
Consecutive Nights Below -40C
In addition, the locales of Mayo and Dawson suffered through 16 consecutive nights dipping under the minus 40 Celsius threshold, with Mayo experiencing a low of -50.4C at the start of the week. Whitehorse similarly reported a series of ten nights when readings fell to minus 30 degrees or lower.
The deep freeze spread farther south through Christmas week. In Edmonton, the Christmas overnight low dipped under -28 degrees Celsius.
The day after Christmas was forecast to deliver lows of at least -20C in numerous areas, encompassing cities from Edmonton to Quebec.
Likely to Linger For Days to Come
This harsh winter weather is expected to continue through the start of January. Officials have warned that the Yukon could face electricity outages over the next several days, as the system endures record-high pressure from peak power usage levels.
The prolonged chill has been caused by the polar vortex remaining anchored over Canada for much of December, allowing bitter Arctic air to spill south. The frigid dome is projected to gradually withdraw north allowing more temperate air from the Pacific to sweep across the United States and penetrate southern Canadian regions.
Pronounced Disparity Compared to Stateside Temperatures
Conversely, sections of America recorded the hottest December 25th in their history as the mercury climbed roughly 15 to 30 degrees above typical averages. In many areas, conditions felt more typical of April or May rather than the end of December.
Multiple states established new Christmas temperature highs. The capital of Oklahoma soared to 25C on Christmas Day, 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 Drives the Heat
Warmer-than-normal conditions are forecast to last on December 26th and into the weekend, with unseasonable heat forecast to sweep across the southeastern US in the coming days.
The unseasonable temperatures are powered by a robust atmospheric ridge extending from the desert south-west towards the north and east, establishing a classic heat-dome pattern. This pattern establishes a broad area of high pressure blanketing a significant part of the landmass, trapping warm air near the surface. Sinking atmospheric air undergoes compression and additional heating, fostering the buildup of exceptional warmth.
