• Air
masses have fairly uniform temperature and moisture content in horizontal direction (but not
uniform in vertical).
• Air
masses are characterized by their temperature and humidity properties.
• The
properties of air masses are determined by the underlying surface properties where they
originate.
•Once formed, air masses migrate within the general
circulation.
•Upon movement, air masses displace
residual air over locations thus changing temperature and humidity characteristics.
•Further, the air masses themselves
moderate from surface influences.