If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Peradeniya: The hottest months are usually March and April with an average temp of 76°F, while the coldest months are January and February with an average of 74°F. The rainiest months in Peradeniya are November, October, December, and April, with each month seeing an average of 14 inches of rainfall.