0 a large area of air that has nearly the same temperature and humidity at any height
1 a large area of air that has nearly the same temperature and humidity at any height
The diagram on the left shows the path of the air mass during the preceding 6 days.
This could only be done even roughly if information was available about the sea temperature at places where the air mass had been a t previous times during its approach.
If the air mass is colder than the ground below it, it is labeled k.
Moisture is removed and latent heat released as the air mass is orographically lifted.
The warmer air near the surface expands, becoming less dense than the surrounding air mass.
It lies within a sharp trough, but the air mass behind the boundary can be either warm or cold.
Subsidence will generally dry out an air mass by adiabatic (compressional) heating.
As the front moved north, a warm, moist air mass expanded over the southern two-thirds of the state.
