June in Yamaguchi is the cloudiest month of the year. In June, the weather in Yamaguchi is typically warm. Average daily high temperature in June is about 23 degrees above zero. On average, Yamaguchi has 21 rainy, 5 cloudy, 3 sunny, and 1 partly cloudy day in June. The rains are usually heavy. June as well as January, February, March, and July is considered the most uncomfortable time to visit Yamaguchi.