The temperature in the Maldives remains pretty constant throughout the year with daytime temperatures around 30°C and night time ones of around 24°C. The humidity is fairly high but the sea breezes keep the air moving and the heat down. The rainy season runs from May to October when rough seas and high winds are possible, although there is likely to be at least a few hours of sun every day too. The dry season runs from January to March, when thunderstorms are greeted as a short and welcome respite from the sun!
December to March are the most popular months with Christmas and New Year being the most expensive times to visit. Prices tend to be fairly constant the rest of the time. November and April are touted by divers as the best times to take a holiday in the Maldives because of the clarity of the water. But that doesn't mean you should write off the rest of the year, there will always be sun, sand and corals to dive even if it does rain a little more.