May in Rach Gia is the rainiest and the cloudiest month of the year. In May, the weather in Rach Gia is typically hot. Average daily high temperature in May is about 31 degrees above zero. On average, Rach Gia has 31 rainy days in May. The rains are usually heavy. May as well as April, June, July, and August is considered the most uncomfortable time to visit Rach Gia.