The wet season, monsoon season or rainy season is the time of year when most of a region’s average annual rainfall occurs. It usually lasts one or more months. The term “green season” is also sometimes used as a euphemism by tourist authorities. Areas with wet seasons are dispersed across portions of the tropics and subtropics. Under the Köppen climate classification, for tropical climates, a wet season month is defined as a month where average precipitation is 60 millimetres or more.