Under the Köppen climate classification, Quito has a Subtropical highland climate. Because of its elevation and its proximity to the equator, Quito has a fairly constant cool climate, with spring-like weather year-round. The average temperature at noon is 18.7 °C (65.7 °F) with a normal night-time low of 9.3 °C (48.7 °F). The annual average temperature is 14.0 °C (57.2 °F). The city experiences only two seasons: dry and wet. The dry season, June through September (4 months), is referred to as summer; the wet season, October through May (8 months), is referred to as winter. Annual precipitation, depending on location, is approximately 1,010 mm (40 in).