With the deep frost (including -7 degrees without windchill), to give the bees an extra helping hand, they got some extra warmth.
The bees basic warmth comes from the bees clustering together and eating honey to maintain 92 degrees around them. The rest of the hive is cold … freezing. The hive is wrapped in tar paper to absorb any sun.
The extra help is from a 15-watt bulb place under the hive. Since the bottom of the hive is screening, which is necessary for the hive to “breathe”, it allows the bulb heat to rise into the hive. To keep the bees in the hive’s natural darkness, the bulb is wrapped in aluminum foil, to only allow the heat.
I hope this extra work allows the bees to make it through the winter.