The official temperature at the airport with a single gravel runway was minus 54 degrees. A cold snap gripping interior Alaska is bothering even longtime residents such as Erickson. Clouds, however, provide an insulating layer reflecting back heat generated by the Earth's crust. Children enjoy recess outside until it hits minus 20, according to Fairbanks school district policy. Tires flatten on the bottom, leading to a bumpy ride until they snap back into shape. Changing a tire, and spinning a metal lug nut, can frostbite a bare finger. If a furnace fails, water pipes can freeze and then burst when they're thawed. Erickson said she had to look at summer pictures of boats, blueberries and kids swimming to help her make it through the day.