January in Thessaloniki is the coldest month of the year. In January, the weather in Thessaloniki is typically cold. Average daily high temperature in January is about 7 degrees above zero. On average, Thessaloniki has 15 partly cloudy, 10 sunny, 4 rainy, and 2 cloudy days in January. The rains are usually light. January as well as February, March, and December is considered the most uncomfortable time to visit Thessaloniki.