The North American continent encompasses several different climates, but most of the continent experiences a temperate climate. Parts of California experience a desert climate, Northern Canada has a polar climate and some of the Californian coast experiences a Mediterranean climate.
A temperate climate, which is found throughout most of North America, is characterized by a lack of extremes in temperature and precipitation. There are distinct summers and winters, but these are not terribly extreme. There are two subtypes of temperate climate. A maritime climate, found predominantly in the Western United States, shows less seasonal variation in temperature than a continental climate, found in the Eastern United States.
In order to be classified as a desert, an area must receive less than 10 inches of rain per year. Deserts tend to be cold at night and very hot during the day. Some parts of California meet this definition, while some coastal regions are classified as having a Mediterranean climate. This climate is characterized by hot summer droughts and heavy winter rain.
Southern portions of Canada experience a temperate climate, but the most northern regions experience a polar climate. Polar climates are characterized by year-round snow and ice cover, and by temperatures that rarely rise above freezing.