There's nothing like an all-inclusive holiday in Waisai to rejuvenate you, especially when you know what kind of weather to expect. Here's some information to help you decide when to book: The hottest months are usually October and May, with an average temperature of 27°C, while the coldest months are July and August, with an average of 26°C. October and February are the driest months, while April and May are the rainiest months.