October in Sillamjae is the rainiest month of the year. In October, the weather in Sillamjae is typically cold. Average daily high temperature in October is about 8 degrees above zero. On average, Sillamjae has 18 rainy, 8 cloudy, 3 partly cloudy, and 2 sunny days in October. The rains are usually heavy. October as well as September, November, and December is considered the most uncomfortable time to visit Sillamjae.