Weather is probably a major factor when you plan your trip to Kieta, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually January and February with an average temp of 78°F, while the coldest months are September and August with an average of 76°F. The rainiest months in Kieta are August, April, July, and March, with each month seeing an average of 22 inches of rainfall.