March in Unawatuna is the hottest month of the year. In March, the weather in Unawatuna is typically hot. Average daily high temperature in March is about 29 degrees above zero. On average, Unawatuna has 25 rainy, 5 sunny, and 1 partly cloudy day in March. The rains are usually heavy. March as well as April, May, June, and July is considered the most uncomfortable time to visit Unawatuna.