Weather will likely play an important role when you plan your trip to Fanning Island, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually June and July, with an average temperature of 28°C, while the coldest months are January and February, with an average of 27°C. The rainiest months in Fanning Island are May, April, March and June, with each month seeing an average of 292 mm of rainfall.