Weather is probably a major factor when you plan your trip to Banjarbaru, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually October and September with an average temp of 80°F, while the coldest months are July and August with an average of 79°F. The rainiest months in Banjarbaru are December, March, January, and November, with each month seeing an average of 15 inches of rainfall.