March in Seaside is the rainiest month of the year. In March, the weather in Seaside is typically cold. Average daily high temperature in March is about 9 degrees above zero. On average, Seaside has 26 rainy, 4 sunny, and 1 cloudy day in March. The rains are usually heavy. March as well as January, February, April, and October is considered the most uncomfortable time to visit Seaside.