If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Pekanbaru: The hottest months are usually May and August, with an average temperature of 27°C, while the coldest months are January and February, with an average of 26°C. The rainiest months in Pekanbaru are November, December, April and October, with each month seeing an average of 332 mm of rainfall.