- Maritime: air masses that form over oceans
- Polar: air masses formed north of 50 degrees north latitude and south of 50 degrees south latitude
- Tropical: warm air masses formed in the tropics and have low air pressure
- air mass: a huge body of air that has similar temperature, humidity, and air pressure
- anticyclone: high pressure center of dry air that spirals outward from the center
- continental: air masses that form over land, in the middle of continents, and are dry
- cyclone: swirling center of low air pressure, from Greek word meaning "wheel"
- front: the area where the air masses meet and do not mix
- occluded: the warm air mass is cut off from the ground