Here's a plot of the daily duration of solar heating at 65N (latitude of Fairbanks), defined as the duration the sun is 5° or more above the horizon. Note the plot extends for 15 months so to show the winter minimum. We are a week into the two months with no significant solar heating. Changes in surfaces temperatures during this time are modulated by horizontal movement of air (advection), vertical mixing (mostly wind) and presence of absence of clouds significant to reduce the continuous cooling of the top of the snow pack (long wave radiation).