It's time for another mention of northern Alaska's "pole of cold" for measured wind chill, i.e. Howard Pass. As noted by reader Gary, conditions have been harsh up there in recent days. In typical fashion, strong northerly winds funneled cold air through the pass (elevation near 2000 feet) with great ferocity starting last Saturday evening, and it wasn't until yesterday afternoon that the wind chill rose above -60°F for the first time in over 3 days.
The minimum wind chill based on hourly mean temperature and wind speed was -73°F on Sunday evening (-25°F temperature, 80mph wind). This is respectable but not all that unusual for the location; wind chills this cold or colder are observed at least once in nearly every winter.
The MSLP analysis from Environment Canada shows the very typical setup at 4pm Sunday, with a very tight pressure gradient caused by a ridge to the north and sprawling low pressure across southern Alaska.
In the 2012-present history of the NPS instruments at Howard Pass, -60°F wind chill has been observed as early as November 17 (2021) and as late as April 9 (2013). As one might expect, it's most common in January and February. Interestingly, this is the first time the wind chill has stayed below -60°F continuously for more than 80 hours this early in the season. However, late November 2021 saw a much more prolonged period of substantial cold, with 11 straight days having a wind chill reading below -60°F at some point in the day.
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