Sri Lanka´s climate is tropical with varying rainfall degrees dependent on the monsoons. Its position between latitudes 5° and 10°N provides a warm climate with mild seabreezes and high air humidity. The mean temperatrures range from 16° Celsius in Nuwara Elliya on the central highlands (which may even display snow and frost in winter) to 32° Celsius in Trincomalle on the island´s northeastern coast. The overall average annual temperature for the island is 28 to 30° Celsius. January is the coldest month while May is the warmest.

While the southwestern part of the island has a year-long humidity with two rainfall maxima in May and October, the southwestern monsoon provides fewer precipitations at the northeastern and eastern coasts since that artea lies on the leeside of the central mountains. There, most rainfalls occur during the north east monsoon period in November and December. The rainfall pattern is influenced by the monsoon winds from the Indian Ocean and the Bay of Bengal and is determined by four seasons. In the first season (May to October), southwestern winds arte carrying humidity from the Indian Ocean. When these winds meet the cntral highlands, heavy downpours are at the mountains and on the south western part of the island. The easternn and northeastern parts of the island will receive little rain during that period. In the second season (October to November), gales and sometimes even cyclones will occur repeatedly and bring dark weather to the island. In the third season (December to March), the northeast monsoon brings humidity from the Bay of Bengal to the northern and northeastern parts of the island. The last season (March to May) sees little rainfalls.