The Central Highlands of Sri Lanka act as the major climatic barrier for the monsoonal winds. This is also the major factor discriminating the two major climate zones of the country, namely: Wet Zone and Dry Zone. Colombo City is in the Wet Zone (mostly comprised by the south-western part of the island), which is exposed to the southwest monsoon (SWM) winds. Apart from the SWM, the first inter-monsoon also produces high rainfall in the Wet Zone [20].