The weather in Sri Lanka is dictated by two monsoon seasons which bring rain to the west and south-west coasts from May to September (South west Monsoon); and the east coast and northern region between October and February (North east monsoon). The rest of the year is sunny and dry. Temperatures are fairly constant year round, with coastal regions enjoying average temperatures of 25-30°C and the highlands 15-18°C on average.
Unlike many other Asian destinations, Sri Lanka can lay genuine claim to being a year-round holiday destination. You just have to know which side of the island to focus on in any given month, and this is never more important than when planning your beach destination.
In the north and eastern coastal regions of the country, the weather is influenced by the north-eastern monsoon, which brings wind and rain between October and January, and drier weather between May and September.