101-8 Air Masses & Fronts Flashcards
Air Mass
(AMS)
A body of air with uniform temperature and moisture
Definition of a Front & Four types
Boundary between two Air Masses (AMS)
1. Cold
2. Warm
3. Stationary
4. Occluded
Frontolysis
Dying/dissipating front
Decrease in significant weather
Frontogenesis
Beginning of a front
Significant weather will increase
Frontal Weather Discontinuities
-Temperature: if greater than or = to 5 degrees C across the front, expect mod or greater turb (MOGR TURB)
-Dew Point: Changes w/ moisture content
-Pressure: may increase or decrease
-Wx: all dependent
(!)- Wind direction ALWAYS changes with frontal passage
Frontal Wave
-Strong indication of weather forming
-Usually form on slow moving cold fronts/stationary
-Precludes a low pressure system
Dry Line
- Moist air from Gulf of Mexico abuts layer of dryer/more dense aire flowing from the SW
-Very similar air characteristics, besides moisture content
-moist air is pushed aloft creating very bad storms
Occluded Front
Closing together of joining fronts (cold overtakes cool overtaking warm)
Stationary Front
When neither AMS overtakes the other
Warm Front
Slower than cold fronts
Cold Fronts
Often lies in a TROF
Wind speed is perpendicular to f font above frictional layer
-fastest of the fronts