Weather is probably a major factor when you plan your trip to Attapeu, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually March and April with an average temp of 81°F, while the coldest months are January and December with an average of 75°F. The rainiest months in Attapeu are July, August, September, and June, with each month seeing an average of 22 inches of rainfall.