Air Masses and Fronts Notes Entry 25 11/28/18 Key Points: Air Masses Air Mass Formation Naming Air Masses Fronts Cold Front Warm Front Stationary Front Occluded Front

1. Air Mass A. Air masses take on the characteristics of the area where they form. B. The temperature and moisture (humidity) remain the same throughout the air mass.

2. Air Mass Formation A. Warm air mass forms over tropical or hot regions. B. Cold air mass forms over polar or cold regions. C. Wet air mass forms over water. D. Dry air forms over land.

3. Naming Air Masses A. The moisture level is represented by the first letter (lowercase) m – maritime – (wet) c – continental – (dry) The temperature level is represented by the second letter (uppercase) 1. P – polar – (cool) 2. T – tropical – (warm)

3. Naming Air Masses C. Types of Air Masses 1. mP – maritime polar air mass, which means wet and cold 2. cP – continental polar air mass, which means dry and cold 3. mT – maritime tropical air mass, which means wet and warm 4. cT – continental tropical air mass, which means dry and warm

4. Fronts A. A front is a boundary or separation between air masses that forms when two different air masses meet B. There are four types of fronts. 1. Cold Front 2. Warm Front 3. Occluded Front 4. Stationary Front

5. Cold Front A. A cold air mass meets a warm air mass and the dense cold air mass pushes the warm air mass out of its way.

5. Cold Front B. Cold fronts lead to thunderstorms, rain or snow C. After a cold front has passed, cooler and drier air follows behind

6. Warm Front A. A warm air mass meets a cold air mass and the light warm air mass rises above the cold air mass.

6. Warm Front B. Warm fronts lead to drizzly precipitation C. After a warm front has passed, clear and warm weather follows behind

7. Stationary Front A. Cold air meets warm air, and there is not enough force to move either front B. Stationary fronts lead to many days of cloudy, wet weather

8. Occluded Front A. Warm air is blocked in between two cold air masses B. Occluded fronts leads to cool temperatures with large amounts of rain or snow