The climate of Switzerland north of the Alps is temperate but varies with altitude, wind exposure, and other factors; the average annual temperature is 9° C (48° F ). The average rainfall varies from 53 cm (21 in) in the Rhône Valley to 170 cm (67 in) in Lugano. Generally, the areas to the west and north of the Alps have a cool, rainy climate, with winter averages near or below freezing and summer temperatures seldom above 21° C (70° F ). South of the Alps, the canton of Ticino has a warm, moist, Mediterranean climate, and frost is almost unknown. The climate of the Alps and of the Jura uplands is mostly raw, rainy, or snowy, with frost occurring above 1,830 m (6,000 ft).