Air Masses and Weather â¢ There are 5 types of air masses: â Continental Arctic (cA): originate in the arctic regions, â¢ Extremely cold and since cold air is incapable of holding moisture it is also very dry. â¢ Though they may warm slightly as they move southward they still cause extreme cold waves in regions they enter. â Continental Polar (cP): originate over land areas of Alaska and Canada. â¢ These air masses are somewhat warmer than cA there is only a slight difference between temperature and humidity of these two types of air masses. â¢ Though this air is cold and dry it will create precipitation in some regions. â¢ One such region is when it passes over the Great Lakes in the fall, the warm water warms the air slightly that it can hold water vapor and then deposits the moisture downwind, creating the lake-effect snows.