30/12/2015
Climate of Sri Lanka
Temperature
Average temperature is 27.5 Celsius at the lowland ( 100-150 meters from the mean sea level) area, but temperature drops quickly with the increasing altitudes. In NuwaraEliya ( At 1800 meters above from mean sea level) average temperature is 15.9 Celsius. If a traveler travel from east coast to west coast across the central mountain range, he can experience hot, next cool and finally again hot environment, within a single day.
Rainfall
Average rainfall is between 900 mm to 5000 mm annually. Eastern coasts gets lesser average rainfall (900 mm) while western coast and western flank of central mountain range gets more rain (2500 mm). In special places like Yatiyantota, Deraniyagala and Watawala gets more rain as 5000 mm.
Wind
Southwest monsoon- during May to September
Northeast monsoon- during December to February
From May to September, southwest or summer monsoon brings heavy rains to western flank of central mountain range and to west coast of Sri Lanka. During this period, west coast gets rain, cloudy sky with turbulent sea areas. So, you should avoid travelling in west coast during summer monsoon. But you are warmly welcomed by the east coast of Sri Lanka with bright, shining skies. You should go there at that time. But......
December to February, north east or winter monsoon winds bring rain to east side of Sri Lanka. You will not be able to enjoy the east coast during these days. So, you can start your journey to west and south coast of Sri Lanka from October to February.