December in Kalispell is the most freezing month of the year. In December, the weather in Kalispell is typically freezing. Average daily high temperature in December is about 1 degree below zero. On average, Kalispell has 10 cloudy, 9 partly cloudy, 7 snowy, 3 sunny, and 2 rainy days in December. The snowfalls are usually moderate. December as well as January, February, March, and April is considered the most uncomfortable time to visit Kalispell.