Download Fronts and Clouds PPT - Effingham County Schools

Fronts & Clouds
• An air mass is a large body of air that
has the same moisture and
temperature throughout.
• A front is the boundary that forms
where two different air masses meet.
• A front that forms when a warm air
mass is trapped between cold air
masses and forced to rise is called an
occluded front.
• A cold front occurs when a cold air
mass meets and displaces a warm air
mass.
• When a warm front and cold front
collide, the cold front forces the
warm air up. The warm air cools so
it cannot hold as much water so it
begins to rain.
• A cold front causes heavy rain
because a cold air mass pushes a
warm air mass higher. As the warm
air mass rises it cools, it cannot hold
as much water. When the air rises,
the water vapor in the air condenses
and the water becomes heavier and
falls to the ground as precipitation.
• All clouds are water molecules that
condensed from water vapor.
• Clouds can form very close to the
surface of the earth as fog.
• Fog is simply a low stratus cloud.
• Rain clouds form when water
droplets condense from water vapor
in the atmosphere
• Nimbus means Precipitation, Rain.
• Cirro means Thin, feathery, wispy
cloud that is very high and no rain is
expected.
• Alto means medium altitude.
• Strato means Spread Out, forms
layers.
• Puffy white clouds with flat bottoms
are called cumulus.
• Thin feathery clouds made of mostly
ice are called cirrus.
• Large thunderhead clouds that
produce precipitation are called
Cumulonimbus clouds.