May in Hải Dương is the windiest month of the year. In May, the weather in Hải Dương is typically hot. Average daily high temperature in May is about 30 degrees above zero. On average, Hải Dương has 26 rainy, 4 sunny, and 1 cloudy day in May. The rains are usually heavy. May as well as June, July, August, and September is considered the most uncomfortable time to visit Hải Dương.