January in Barcelona is the sunniest and the coldest month of the year. In January, the weather in Barcelona is typically warm. Average daily high temperature in January is about 25 degrees above zero. On average, Barcelona has 21 sunny, 8 partly cloudy, 1 rainy, and 1 cloudy day in January. The rains are usually light. January as well as February and March is considered the most comfortable time to visit Barcelona.