Climate
The Köppen classification depends on average monthly values of temperature and precipitation. The most commonly used form of the Köppen classification has five primary types labeled A through E. These primary types are A) tropical, B) dry, C) mild mid-latitude, D) cold mid-latitude, and E) polar. The five primary classifications can be further divided into secondary classifications such as rainforest, monsoon, tropical savanna, humid subtropical, humid continental, oceanic climate, Mediterranean climate, desert, steppe, subarctic climate, tundra, and polar ice cap.
Continental climate
Most such areas fit Köppen classifications of Dfa, Dwa (cold winters, hot summers; "w" indicating very dry winters characteristic especially of China) or Dfb or Dwb (cold winters, warm summers, same distinction for winter dryness). Dry summer continental climates (Dsa and Dsb) exist in high altitude areas near Mediterranean climates. In some cases, the semi-arid climate classification of BSk can also be considered to be continental as long as it has cold winters. The definition of this climate regarding temperature is as follows: the mean temperature of the coldest month must be below and there must be at least four months whose mean temperatures are at or above .