<P> Quito's closest volcano is Pichincha, looming over the western side of the city . Quito is also the only capital in the world to be directly menaced by an active volcano . Pichincha volcano has several summits, among them Ruku Pichincha at 4,700 metres (15,400 feet) above sea level and Wawa Pichincha at 4,794 metres (15,728 feet). Wawa Pichincha is active and being monitored by volcanologists at the geophysical institute of the national polytechnic university . The largest eruption occurred in 1660 when more than 25 cm (9.8 in) of ash covered the city . There were three minor eruptions in the 19th century . The latest eruption was recorded on October 5, 1999, when a few puffs of smoke and a large amount of ash were deposited on the city . </P> <P> Activity in other nearby volcanoes also can affect the city . In November 2002, after an eruption in the volcano Reventador, the city was showered with a layer of fine ash particles to a depth of several centimeters . </P> <P> The volcanoes on the Central Cordillera (Royal Cordillera), east of Quito, surrounding the Guayllabamba valley include Cotopaxi, Sincholagua, Antisana and Cayambe . Some of the volcanoes of the Western Cordillera, to the west of the Guayllabamba valley, as well as are Pichincha include Illiniza, Atacazo, and Pululahua (which has the Pululahua Geobotanical Reserve). </P> <P> Under the Köppen climate classification, Quito has a subtropical highland climate (Cfb). Because of its elevation and proximity to the equator, Quito has a fairly constant cool climate . 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 ° C (57 ° F). 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 1,000 mm (39 in). </P>

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