August in Haiphong is the rainiest month of the year. In August, the weather in Haiphong is typically hot. Average daily high temperature in August is about 32 degrees above zero. On average, Haiphong has 26 rainy, 3 cloudy, 1 sunny, and 1 partly cloudy day in August. The rains are usually heavy. August as well as May, June, July, and September is considered the most uncomfortable time to visit Haiphong.