CLOUDS Chapter 11.3 notes Mr.Allbee

Cloud Formation Clouds form as warm moist air is forced upwards, cools and water vapor condenses to form tiny water droplets. Millions of tiny water droplets gather together to form a cloud

Cloud Formation Dry Adiabatic Lapse Rate – how fast unsaturated air will cool as it rises DAR = 100C for every 1000m rise The height at which the dew point is reached and a cloud begins to form, the Lifted Condensation Level (LCL) has been reached. Usually, the LCL is marked by the base or bottom of the cloud Moist Adiabatic Rate - how fast saturated air cools above the LCL MAR = avg. 60C for every 1000m rise

Cloud Formation Orographic Clouds are clouds that are formed as moist air rises over mountains or other major geographic features. The air floats up the side of the mountain and cools quickly, condensing and turning into a cloud.

Cloud Classification Two common ways to classify clouds: 1. By Their Shape Stratus Cumulus Cirrus 2. By Their Height Cirro Alto Strato

Stratus Clouds

3 Cloud Types Based on Shape 1. Stratus Form in layers or smooth even sheets Usually low altitude clouds Associated with fair weather or drizzle Sometimes forms a gray blanket covering the entire sky and produces light rain or drizzle

Cumulus Clouds

3 Cloud Types Based on Shape 2. Cumulus Masses of puffy white clouds Associated with fair weather but may possibly produce thunderstorms

Cirrus Clouds

3 Cloud Types Based on Shape 3. Cirrus High, thin, white, feathery clouds Associated with fair weather Indicate that bad weather may be approaching

Height – Prefixes for Cloud Base Cirro – High Level Clouds Alto – Middle Level Clouds Strato – Low Level Clouds

Other Types of Clouds Vertical Development Nimbus High, towering clouds usually with a low altitude base Nimbus Dark clouds associated with heavy rain and storm

10 Common Cloud Names Cirrus Cirrostratus Cirrocumulus AltoStratus Altocumulus Cumulus Stratocumulus Nimbostratus Cumulonimbus

Altocumulus Clouds

Altostratus Clouds

Cirrocumulus

Cirrostratus Clouds

Cirrus Clouds

Cumulonimbus Clouds

Cumulus Clouds

Stratus Clouds

Nimbostratus Clouds

Stratocumulus Clouds