Weather is probably a major factor when you plan your trip to Lighthouse Reef, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually September and August, with an average temperature of 27°C, while the coldest months are January and December, with an average of 24°C. The rainiest months in Lighthouse Reef are June, October, September and August, with each month seeing an average of 266 mm of rainfall.