AIR MASSES, FRONTS, AND TYPES OF CLOUDS*

Used with permission of V. Morris, Phillips Preparatory School

An air mass is a large body of air. Air mass temperature and moisture are consistent.

Warm air forms over tropical regions near the equator. Cold air forms over polar regions.

Wet air masses form over water Dry air masses from over land. *

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A front is a boundary between air masses.There are 2 main types of fronts: Cold frontWarm front*

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.

Cold front followed by cooler drier air.

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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.*

Cold Front, Warm Front and Occluded Front Animation

http://www.classzone.com/books/earth_science/terc/content/visualizations/es2002/es2002page01.cfm?chapter_no=visualization

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CloudsThere are 3 main types of clouds:Cumulus Stratus Cirrus

Used with permission of V. Morris, Phillips Preparatory School

CirrusThey ususally indicate cool, fair weather.

Used with permission of V. Morris, Phillips Preparatory School

Stratus CloudsLow clouds that can produce mist or drizzle. However, when temperatures are cold enough, these clouds may also contain ice particles and snow. They often occur along warm fronts.

Used with permission of V. Morris, Phillips Preparatory School

Stratus Clouds

Used with permission of V. Morris, Phillips Preparatory School

Cumulus Clouds They are puffy in appearance. They look like large cotton balls. Harmless fair weather cumulus clouds can later develop into towering cumulonimbus clouds associated with powerful thunderstorms.

Used with permission of V. Morris, Phillips Preparatory School

Cumulus

Used with permission of V. Morris, Phillips Preparatory School

Used with permission of V. Morris, Phillips Preparatory School

Used with permission of V. Morris, Phillips Preparatory School

CLASS ACTIVITY1. Read Job 37:11 He loads the clouds with moisture; He scatters his lightning through them.2. Now, illustrate and explain the kind of cloud that is being described in the passage.

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Class Activity1. What are barometers and anemometers? (page 398)Exercise 2, 3, and 4 on the pages 68 and 69. (Reading Support and Homework)

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