August in Seabrook is the rainiest and the hottest month of the year. In August, the weather in Seabrook is typically hot. Average daily high temperature in August is about 33 degrees above zero. On average, Seabrook has 15 rainy, 10 sunny, and 6 partly cloudy days in August. The rains are usually heavy. August as well as June, July, and September is considered the most uncomfortable time to visit Seabrook.