January in Rayakoski is the cloudiest and the most freezing month of the year. In January, the weather in Rayakoski is typically freezing. Average daily high temperature in January is about 8 degrees below zero. On average, Rayakoski has 20 cloudy, 9 snowy, and 2 sunny days in January. The snowfalls are usually light. January as well as April, May, June, and July is considered the most uncomfortable time to visit Rayakoski.