Some love it, some hate it, but most people in Whitehorse can agree on this much — the weather this week has been strange for December.

After some bracing winter weather in November, the city has seen an unusually mild start to this month, with temperatures soaring well above the freezing point, and even some rain.

Whitehorse broke a 57-year-old record on Wednesday, when the mercury reached 5.9 C in the late afternoon (the previous record was 4.4 C, set in 1960). It was the city's warmest Dec. 6 since 1900, and about 15 degrees warmer than average, for early December.

Thursday could be another record-breaker, with a forecast high of 7 C.

Matt MacDonald, an Environment Canada meteorologist, attributes it to "a really impressive ridge of high pressure" over western Canada, bringing warm air up from Mexico.

Matt MacDonald

Environment Canada meteorologist Matt MacDonald says an intense high pressure system over western Canada has brought warm air up to Yukon. (Steve Hossack/CBC)

"The intensity of this ridge has not been seen, at this time of year, as far as records go back," he said. "This is a perfect example that climate change is real, it is occurring, and is going to continue to happen."

According to MacDonald, the high pressure ridge would happen with or without climate change, but would likely be less intense.

"We'd still be seeing this abnormally warm stretch of weather, but it would probably be maybe closer to –5," he said.

The slushy conditions are expected to continue for at least few more days. Environment Canada is predicting daytime temperatures above 0 C — maybe as high as 8 C on Sunday — until early next week.


  • An earlier version of this story said Whitehorse reached 6.5 C on Dec. 6, 2017, breaking a century-old record. In fact, it reached 5.9 C that day, and the previous record (4.4 C) was set in 1960. The earlier story also said it was the warmest Dec. 6 since 1904. In fact, it was the warmest since 1900.
    Dec 11, 2017 2:20 PM CT
With files from Steve Hossack