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San José, the capital of Costa Rica, sits in the Central Valley (Valle Central) in the middle of the country, on a plateau at around 1,170 metres above sea level, ringed by mountains and volcanoes, at approximately 9.93°N, 84.09°W. Its altitude tempers the tropical latitude to give a mild tropical highland climate (Köppen Aw/Cwb) — spring-like year-round — with a warm dry season and a warm wet season rather than any change of temperature.
There is no summer in the temperate sense: temperatures stay mild and spring-like all year, with daytime highs around 26–27°C and cool nights near 16–17°C, thanks to the elevation. The wet season, from May to November — the local 'green season' — brings warm mornings that cloud over into heavy afternoon and evening downpours and thunderstorms, with September and October the wettest months, while mornings often stay bright.
There is no true winter, but the dry season from December to April brings warm, sunny, breezy days with little rain and lower humidity — the most popular time to visit. Temperatures barely change from the wet season, staying pleasantly mild, but the skies are clearer and the afternoons drier, making this bright, spring-like stretch the peak tourist season in the Central Valley.
San José receives on the order of 1,800–2,000 mm of rain a year, overwhelmingly concentrated in the wet season from May to November, with September and October the wettest, while December to April is markedly dry; the rain typically falls in heavy afternoon bursts after sunny mornings. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.
San José's Central Valley altitude gives it the mild, spring-like climate for which Costa Rica's highlands are famous — never truly hot, never cold — with the year divided simply into a sunny dry season and a green, rainy 'invierno'. The surrounding mountains create sharp rain-shadow contrasts, so weather can differ markedly between the valley and the wetter slopes just a short drive away.
To follow any single measurement in San Jose more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.