The climate of London is broadly similar to the rest of the UK, with warm summers, cool winters, no wet or dry season, and often moderate to strong winds. It is classed as a temperate maritime climate according to the Köppen climate classification system. In terms of the local climate profile, the temperature tends to increase towards the centre of the urban area, primarily because of the urban heat island effect, but also because London's topography results in the central area being the lowest part of the region in terms of altitude.