Fairbanks and Anchorage woke Wednesday to the deep-freeze of an expected cold snap this week, as temperatures plunged to 50 degrees below zero in some areas of the Interior.
The lowest temperature recorded by the National Weather Service Wednesday morning was 59 below on the Salcha River near its confluence with Flat Creek, said meteorologist Dan Hancock in the agency's Fairbanks office.
By 4 p.m., the temperature on the Salcha had risen 20 degrees — to 39 below, Hancock said.
The Fairbanks weather service office issued a dense fog advisory Wednesday afternoon that was in place until midnight. Visibility of a quarter-mile or less was expected from Fairbanks to Eielson Air Force Base, primarily in lower elevations.
Air quality in North Pole was considered unhealthy; Fairbanks air quality was moderate, according to the Fairbanks North Star Borough's air quality forecast.
Other low temperatures were recorded throughout Fairbanks. Fort Wainwright hit a low of minus 52 around 9 a.m. Wednesday morning, and Eielson hovered around 51 below for most of the morning, Hancock said.
Fairbanks International Airport recorded 51 below around 10 a.m. The last time the airport temperature dropped that low was in January 2012, Hancock said.
The temperatures were recorded by remote automated weather stations, which are considered reliable even in extreme cold, unlike some thermometers, Hancock said.
Christopher Cox, lead meteorologist at the Fairbanks office, discounted Interior reports on social media late Wednesday morning of 60-below readings, saying they were likely based on electronic thermometers that become unreliable at 40 below.
"We've got thermometers that are reading 60 below, but they're inaccurate," Cox said. "We're going to be close (to that temperature) in some of the outlying spots, but not for Fairbanks."
Eastern Interior, morning lows ranged from minus 44 below in Ambler and Shungnak to 45 below in Galena, 47 below in Kaltag and 51 below in McGrath, Huslia and Nikolai.
Thursday's temperatures were forecast to remain frigid, with a high subzero temperature around 40 below, and patchy ice fog.
In Southcentral, the Talkeetna airport bottomed out at 32 below around 10 a.m., said Eddie Zingone, meteorologist at the Anchorage NWS office.
Wasilla's lowest temperature Wednesday was 29 below, around 8 a.m. Palmer got down to 23 below, around the same time, and on Wednesday evening temperatures were still hovering at minus 21 degrees in Palmer, Zingone said.
Anchorage's lowest official temperature was 15 below at Ted Stevens Anchorage International Airport around 10 a.m.
Thursday's forecast called for the cold to stick around, with some parts of the city's east side to reach 20 below, and the airport again expected to reach around 15 below, Zingone said.
Jim Brader, a Fairbanks-based NWS meteorologist, said temperatures fell quickly as the cold snap arrived Tuesday, hitting 30 below there by afternoon and 40 below by evening. He said relatively warmer weather should prevail beginning Friday due to cloud cover being brought into the area by two storms.
"There's one in the Gulf of Alaska that's moving into the Yukon territory tonight, and that's moving some clouds into the area along the border — we have another system in the Bering Sea that's starting to spread some clouds into the Yukon-Kuskokwim (Delta)," Brader said. "By the weekend we'll be somewhere in the 0 to 20 below region, which is generally the norm for this time of year."
Clay said Anchorage and much of Southcentral can expect the cold for the next few days.
"We'll have a cold trough that's moving through tonight; it'll still be fairly cold Thursday morning," Clay said. "We're expecting 14 below at the airport, probably in the minus 20s elsewhere."
Southcentral should see the same relief from those lows as the Interior, due to the shifting statewide weather patterns.
"We'll still be looking at single digits — it'll be slowly warming into the weekend," Clay said.