Download Notes: Air masses and fronts Air masses are large bodies of air in

Notes: Air masses and fronts
 Air masses are large bodies of air in which the
temperature and/or the amount of moisture are the same
throughout
 A front is the boundary where different air masses
collide
 A cold front forms when a mass of cold air replaces a
mass of warm air. The cold air dives under the warm air,
pushing it up. The warm air cools and the water vapor
condenses forming clouds and rain. The rain is followed
by the cooler temperatures of the cold air mass.
 A warm front forms when a mass of warm air replaces a
mass of cold air. The warm air slides slowly over the cold
air allowing more water vapor to cool and condense,
forming more clouds and heavier rain. The rain is followed
by warmer, humid weather.
 A stationary front is formed when two air masses meet
and there is no movement. Widespread clouds form on
both sides of the front and often bring a lengthy period
of rain.
 Clouds mainly form on the side of a front where the warm
air mass is as warm air contains more water vapor.