Sri Lanka experiences two monsoon periods every year, one between May and July and the other between December and January. The first monsoon brings most rainfall to the western mountains from May to October, while the second monsoon brings rain to the eastern and northern slopes from December until March. The second monsoon season sees only about half the rainfall of the first.

The months between the two monsoon periods see clear, dry weather. Temperatures are at their highest in April and May, while October and November are considerably cooler. The average annual temperature ranges from 25 to 28 degrees centigrade, with nights being around five degrees cooler on average.