If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Pulau Bunaken: The hottest months are usually September and October, with an average temperature of 27°C, while the coldest months are February and March, with an average of 26°C. The rainiest months in Pulau Bunaken are January, May, December and November, with each month seeing an average of 325 mm of rainfall.