Air masses are large bodies of air that take on the characteristics of the surrounding area or source region. A source region is an area in which the air remains stationary for a few days. Air masses are generally classified by their characteristics. In addition, as air masses move, they can be modified when they move over a region unlike their source region. The boundaries between air masses are called fronts.
|Continental Arctic (cA)||Cold, dry|
|Continental Polar (cP)||Cool, dry|
|Continental Tropical (cT)||Hot, dry|
|Maritime Polar (mP)||Cool, humid|
|Maritime Tropical (mT)||Warm, humid|