Yesterday was the northern hemisphere's winter solstice, when the Earth's tilt is furthest from the sun. The short days and low sun are particularly noticeable at high latitudes. In Fairbanks, there was just three hours and forty-two minutes from sunrise to sunset, and the sun only reached a few degrees above the horizon. This results in very little energy being absorbed by the ground (less than four watts per square meter), and consequently when clouds clear out temperatures can easily fall to forty below zero.
More than in years past the low angle of the sun was particularly noticeable to me. Behind a low hill or looking out an east facing window one might not see any daylight. Even at midday it would appear the sun was setting by its golden glow along the mountains of the Alaska Range.
Due to the elliptical orbit of the Earth, the sun's return is not very fast in winter. While in the spring day length can increase by as much as eight minutes a day, it is currently increasing some number of seconds. January is often the coldest month in Fairbanks, and temperatures to forty below have even been recorded in March.
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