Yellowknife residents can expect temperatures of around -50C with wind chill until at least Wednesday this week, Environment and Climate Change Canada says.
The territorial capital registered a sunny but chilly -38C without wind chill on Monday afternoon, with a low of -39C forecast overnight. Temperatures are not set to break -30C for most of the week.
“Wind chill values have dropped to near -50C today,” the federal agency said in a Monday warning that also extends to Wekweètì, Whatì, Gamètì, and Behchokǫ̀.
“Extreme cold conditions are expected to persist until Wednesday afternoon with slight improvement through daytime periods.”
Wednesday is expected to be the week’s warmest day, with a forecast high in Yellowknife of -29C. Christmas Day is currently forecast to be sunny with a high of -33C.
The threshold for extreme cold warnings varies depending where in Canada they are issued.
In most of the Northwest Territories, they are issued when the temperature – either with or without wind chill – is expected to reach -50C for at least two hours.
In Paulatuk, Sachs Harbour, and Ulukhaktok, such warnings are only issued for temperatures of -55C and lower.
By contrast, temperatures of -30C are enough to trigger the same warning in many parts of Ontario.
Last year, Yellowknife endured a period of brutal cold below -40C in the weeks before the holiday season, but Christmas Day itself reached a high of-15C, as did the same day a year earlier.
If it comes to pass, a high of -33C this year would be Yellowknife’s coldest Christmas Day since 2014, when the city failed to get above -35C without wind chill.