The airmass has finally cooled in earnest in Fairbanks-land, and the effects are showing as skies clear (technical: 12Z 850mb temp -26.7C, 1000-500mb thickness 499dm). Here is the NOAA-19 Polar Orbiter infrared image from just after 5am AST Thursday, as skies were starting to clear just west of Fairbanks.
In the middle Yukon River valley, where it has been cleared for more than a day, valley temperatures were down near 40 below.
By 10am, temperatures in the Fairbanks area were down to 28 below at the Fairbanks Airport, 26 below at Goldstream Creek, 23 below at Keystone Ridge and 19 below on Cleary Summit. The North Pole and Eielson took longer to clear but will soon catch up.