August in Hagatna is the rainiest and the cloudiest month of the year. In August, the weather in Hagatna is typically hot. Average daily high temperature in August is about 29 degrees above zero. On average, Hagatna has 29 rainy and 2 sunny days in August. The rains are usually heavy. August as well as January, June, July, and September is considered the most uncomfortable time to visit Hagatna.