1. Chapter 18 – Water in the Atmosphere
Cloud Formation
Chapter 18 – Water in the Atmosphere

2. Basic Cloud Formation
Warm air (less dense) rises and cools due to elevation change (lapse rate).
Water vapor will condense when moist air is cooled.
Water vapor will condense around condensation nuclei.
Specks become droplets.
Huge numbers of droplets forms clouds.

3. Basic Cloud Formation

4. Daily Cloud Formation Sun’s rays warm the ground causing evaporation.
Warm air rises.
Air cools with higher elevation.
Water vapor condenses to form clouds.

5. Daily Cloud Formation

6. Coastal Cloud Formation
Warm, moist air comes from the ocean.
Warm air clashes with cold dry air on land.
Clouds form.
Common on coastal areas.

7. Coastal Cloud Formation
Warm
Cool, dry

8. Mountain Cloud Formation
Warm, moist air is elevated.
Air cools to dew point because of elevation change.
Clouds form.
Windward vs. Leeward
Windward = rainy
Leeward = dry
Common in mountain areas.

9. Mountain Cloud Formation

10. Frontal Cloud Formation
Cold dense air (cold front) moves in causing warm air to be pushed upward.
Warm air cools with elevation and condenses to form clouds.
Common with arrival of cold front weather systems.

11. Frontal Cloud Formation