January in Matsuyama is the sunniest and the coldest month of the year. In January, the weather in Matsuyama is typically cold. Average daily high temperature in January is about 6 degrees above zero. On average, Matsuyama has 14 sunny, 12 partly cloudy, and 5 rainy days in January. The rains are usually moderate. January as well as February, July, August, and December is considered the most uncomfortable time to visit Matsuyama.