The southern part of Quito has a subtropical highland climate (Köppen climate classification "Cfb"), while the northern part has a warm-summer mediterranean climate (Köppen climate classification "Csb"). Because of its altitude and location on the equator, Quito has a fairly constant cool climate. The average afternoon maximum temperature is , and the average night-time minimum temperature is . The annual average temperature is . The city has 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 about .