Weather will likely play an important role when you plan your trip to Futuna Island, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually February and March with an average temp of 81°F, while the coldest months are August and September with an average of 76°F. The rainiest months in Futuna Island are April, March, January, and February, with each month seeing an average of 11 inches of rainfall.