1. AIR MASSES AND FRONTS
Chapter 16 Section 2

2. Air Mass
A large body of air where temperature and moisture content are similar throughout

3. Air Masses Warm air forms over tropical regions near the equator.
T- Tropical
Cold air forms over polar regions.
P- Polar
Wet air masses form over water
m- maritime
Dry air masses from over land.
c- continental

4. Air masses Moisture content - first letter. m – maritime – wet
c – continental – dry
Temperature - second letter.
P – polar – cool
T – tropical - warm

5. Description of air masses:
Continental polar (cP)- cool and dry
Continental arctic-type of continental polar mass that is much colder-forms in the arctic circle
Continental tropical (cT)- warm (hot) and dry
Maritime polar (mP)- humid (wet) and cold; unstable
Maritime tropical (mT)- humid (wet) and warm; unstable

6. Air Masses mP- maritime polar air mass cP – continental polar air mass
mT – maritime tropical air mass
cT – continental polar air mass

7. An air mass is a large body of air that has similar temperature and moisture properties

9. Fronts A boundary between air masses. Cold front Warm front
Four types of fronts and map symbols
Cold front
Warm front
Occluded front
Stationary front

10. WARM FRONT
Warm air mass meets a cold air mass and pushes the cold air mass out of the way.
Brings drizzly precipitation followed by clear warm weather.

11. Symbol:
Warm Fronts

12. Clouds, Storms, and rain accompany warm fronts.
Warm Front Animation:

13. COLD FRONT
Cold air mass meets a warm air mass and pushes the warm air mass out of its way.
Bring thunderstorms, rain or snow.
Most tornadoes develop from
thunderstorms on the edge of a cold front.
Followed by cooler, drier air.

14. Symbol:
Cold Fronts

15. Cold Fronts can cause heavy snow or ice if there is enough water vapor in the air.

16. STATIONARY FRONT Cold air meets warm air.
Not enough force to move either front.
Many days of cloudy, wet weather.

17. Stationary Front Symbol:
Where they meet, water vapor in the warm air condenses into rain, snow, fog or clouds
Can stall out for days

18. Stationary Fronts: Stationary Front Animation:

19. OCCLUDED FRONT Warm air caught between two cold air masses.
Brings cool temperatures with large amounts of rain or snow

20. Occcluded Fronts: The two cooler air masses meet in the middle and may mix.
The warm air mass is cut off (or occluded) from the ground.

21. Symbol:
Occluded Front

22. Cold Front, Warm Front and Occluded Front Animation
Click on the above links.