If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Arugam Bay: The hottest months are usually June and July, with an average temperature of 29°C, while the coldest months are January and February, with an average of 26°C. The rainiest months in Arugam Bay are December, November, January and October, with each month seeing an average of 324 mm of rainfall.