If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Jayapura: The hottest months are usually October and November, with an average temperature of 26°C, while the coldest months are August and July, with an average of 25°C. The rainiest months in Jayapura are December, March, April and November, with each month seeing an average of 382 mm of rainfall.