If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in South Tangerang: The hottest months are usually September and October, with an average temperature of 28°C, while the coldest months are July and August, with an average of 27°C. The rainiest months in South Tangerang are February, January, March and December, with each month seeing an average of 289 mm of rainfall.