WHEN TO GO TO COOK ISLANDS:

Climate: The Cook Islands climate is tropical oceanic, with two distinct seasons: the cold and dry season that goes from April till November with average maximum temperatures around 26°C and average minimum temperatures around 20°C; the hottest and rainy season ranging from December till March which average maximum temperature around 28°C and average minimum temperatures around 22°C, in this period the islands occasionally can be affected by tropical cyclones and hurricanes. The average annual rainfall is around 2,100 mm, more rainy months are those between December and April, the less rainy months are those between June and October. Anti-mosquito repellents are needed especially during the hot and humid season (December-March), especially on the island of Aitutaki. 

The average annual temperature of the sea water in Rarotonga is 25.9°C, with maximum temperatures of 30.2°C in February and minimum temperatures of 22.0°C in August.