December in Miyako-jima is the windiest month of the year. In December, the weather in Miyako-jima is typically warm. Average daily high temperature in December is about 21 degrees above zero. On average, Miyako-jima has 16 rainy, 6 partly cloudy, 5 cloudy, and 4 sunny days in December. The rains are usually heavy. December as well as January, February, March, and May is considered the most uncomfortable time to visit Miyako-jima.