Amid 24-hour darkness, Alaskan Arctic town reaches 40F (4.4C), setting all-time winter 'heat' record

Scott Sistek
Fox Weather
Tue, 06 Dec 2022 21:15 UTC

© (Bonnie Jo Mount/The Washington Post / Getty Images

In more normal weather Bryan Thomas, right, station chief at the Barrow Atmospheric Baseline Observatory, and Peter Detwiler, technician, perform maintenance checks in Utqiavik, AK on April 11, 2019.

A wind shift turned up the "heat" in Alaska's Utqiagvik — the northernmost town in America — sending the temperature zooming from 25 to a balmy 40 degrees in just 30 minutes.

The northernmost town in Alaska got a brief taste of winter warmth - at least, relatively speaking - when a wind shift brought a surge of mild, above-freezing air to this arctic enclave Monday morning.

Monday began as a typical morning in Utqiagvik - formerly known as Barrow. Temperatures were around 20 but with wind chills near zero as southeasterly winds gusted to 35 mph.

Then, a wind shift out of the south ahead of an approaching band of snow turned up the "heat," sending the temperature zooming from 25 to a balmy 40 degrees in just 30 minutes.

© ACCAP/NOAA NCEI & NWS

December maximum temperature at Utqiaġvik 1920-2022

The reading smashed the town's record for the warmest December day by several degrees, besting the old record of 34 degrees set in 1932. In fact, it was the warmest temperature ever recorded in winter... or even late fall or early spring.

The previously warmest temperature recorded between Oct. 20 and April 22 was 39 degrees, set in November 1937, according to the National Weather Service in Fairbanks, crediting climate specialist Rick Thoman for the find.

But don't think that the town residents all raced outside to party in the streets, sunglasses and beachwear in hand, as Utqiagvik is still amid 65 days of polar darkness and hasn't seen the sun since Nov. 18. (And it won't see a sunrise until Jan. 23.)

Besides, the 40-degree reading only lasted moments, and temperatures gradually cooled back into the 20s by evening with wind chills back in the teens, and temperatures were down into the single digits Tuesday morning.

But it's been part of a mild start to winter in the Arctic. November ranked as the sixth warmest by average temperature, and three of the other five years ahead of it have come since 2017. And Utqiagvik nearly reached the December temperature record on Friday with a high of 32.

See video here.

Comment: A bit more from Rick Thoman on the event:

From his substack:

Why do we see this "ceiling" in high temperature in December? Three factors stand out. First, there's no sunshine at all at Utqiaġvik in December to help boost temperatures. Second, a characteristic of the Arctic and sub-Arctic atmosphere in winter is the very frequent presence of a temperature inversion, where the temperature is lower at the ground than at elevation. This colder dense air is difficult to mix out (or replace) and usually requires a combination of wind and clouds to warm the surface air (in the spring, daytime heating from the sun can help too). And third, as temperatures reach freezing, energy starts to go into warming and (eventually) melting the snow and ice that is always present at Utqiaġvik in winter. The December 5th record temperature was the result of temperature inversion completely breaking, which allowed the very mild air that was already above the surface mix right down to the tundra surface.