December in Karlskoga is the windiest month of the year. In December, the weather in Karlskoga is typically freezing. Average daily high temperature in December is about zero. On average, Karlskoga has 11 rainy, 9 snowy, 6 cloudy, 4 sunny, and 1 partly cloudy day in December. The rains are usually moderate. December as well as March, May, October, and November is considered the most uncomfortable time to visit Karlskoga.