January in Karlovy Vary is the snowiest, the cloudiest, and the most freezing month of the year. In January, the weather in Karlovy Vary is typically freezing. Average daily high temperature in January is about 1 degree below zero. On average, Karlovy Vary has 16 snowy, 11 cloudy, 2 rainy, and 2 sunny days in January. The snowfalls are usually light.