The subtropics are geographic and climate zones located roughly between the tropic circle of latitude (the Tropic of Cancer and Tropic of Capricorn) and the 38th parallel in each hemisphere. Subtropical climate regimes can exist at high elevations within the tropics, such as in the southern end of the Mexican Plateau and in Vietnam and Taiwan. Also places like Hong Kong, although inside the tropics, have a subtropical climate due to the influence of cold Siberian air masses. Six climate classifications use the term to help define the various temperature and precipitation regimes for the planet Earth. Eight months of the year within the subtropics have an average temperature at or above , with their coldest month averaging between .