Weather is probably a major factor when you plan your trip to Bagansiapiapi, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually July and June with an average temp of 80°F, while the coldest months are January and February with an average of 79°F. The rainiest months in Bagansiapiapi are November, December, October, and September, with each month seeing an average of 13 inches of rainfall.