Wet season
 |
| Part of a series on |
| Weather |
|---|
 Weather portal |
A wet season or rainy season is a season in which the average rainfall in a region is significantly increased. The term green season is also sometimes used as a euphemism by tourist authorities.
These terms are commonly used describing the weather in the tropics. Tropical weather is dominated by the movement of the tropical rain belt, which oscillates from the northern to the southern tropics over the course of the year.
The tropical rain belt lies in the southern hemisphere roughly from October to March, and during this time the southern tropics experience a wet season, in which rain is common. Typically, days start off hot and sunny, with humidity building during the day and culminating in large thunderstorms and torrential rain in the afternoon or evening. From April to September, the rain belt lies in the northern hemisphere, and the northern tropics experience their wet season.
The rain belt reaches roughly as far north as the Tropic of Cancer and as far south as the Tropic of Capricorn. Near these latitudes, there is one wet season and one dry season annually. On the equator, there are two wet and two dry seasons as the rain belt passes over twice a year, once moving north and once moving south. Between the tropics and the equator, locations may experience a short wet and a long wet season. Local geography may also substantially modify these climate patterns.
Rainy seasons are not isolated to tropical areas. In temperate Mediterranean climates, there is a clear rainy season in winter and dry season in summer. This same pattern is also seen in some temperate oceanic climate areas, such as Seattle.