January in Banja Luka is the snowiest and the coldest month of the year. In January, the weather in Banja Luka is typically cold. Average daily high temperature in January is about 5 degrees above zero. On average, Banja Luka has 9 partly cloudy, 8 cloudy, 7 sunny, 5 rainy, and 2 snowy days in January. The rains are usually heavy. January as well as February, March, November, and December is considered the most uncomfortable time to visit Banja Luka.