December in Matsuyama is the windiest month of the year. In December, the weather in Matsuyama is typically cold. Average daily high temperature in December is about 9 degrees above zero. On average, Matsuyama has 12 sunny, 11 partly cloudy, and 8 rainy days in December. The rains are usually light. December as well as January, February, July, and August is considered the most uncomfortable time to visit Matsuyama.