The Cape Peninsula has a Mediterranean climate with well-defined seasons. In winter, which lasts from May to August, large cold fronts come across from the Atlantic Ocean with heavy precipitation and strong north-westerly winds. The winter months are cool, with an average minimum temperature of 7 °C (45 °F). Most of the city's annual rainfall occurs in wintertime, but due to the mountainous topography of the city, rainfall amounts for specific areas can vary dramatically. The suburb of Newlands which is to the south of the city is the wettest place in South Africa. The valleys and coastal plains average (20 in) of rain per annum, while mountain areas can average as much as 1,500 millimetres (60 in) per annum. Summer, which lasts from November to February, is warm and dry. The Peninsula gets frequent strong winds from the south-east, known locally as the Cape Doctor, because it blows away pollution and cleans the air. The south-easterly wind is caused by a high-pressure system which sits in the South Atlantic to the west of Cape Town, known as the South-Atlantic High. Summer temperatures are mild, with an average maximum of 26 °C (79 °F).