March in Chilaw is the hottest month of the year. In March, the weather in Chilaw is typically hot. Average daily high temperature in March is about 30 degrees above zero. On average, Chilaw has 17 rainy, 9 sunny, and 5 partly cloudy days in March. The rains are usually heavy. March as well as April, May, June, and July is considered the most uncomfortable time to visit Chilaw.