Cloud Types

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Cloud Types
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Main Classifications
Cumulus puffy clouds, that often have a flat
base. Some people call them cauliflower
clouds. They often have the appearance of
cotton balls. May cause precipitation (see
Nimbus, next slide).
Stratus seemingly endless layers. You cannot
see shapes in stratus clouds because they are
flat. When stratus clouds are low and dark, they
make the day seem dreary. Fog is a stratus cloud
at ground level. May cause precipitation (see
Nimbus, next slide).
Cirrus thin, wispy, often finger-like clouds
that are made of ice crystals. Do not cause
precipitation.
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Naming Clouds
Often the name of a cloud is the combination of
one of the three major types of clouds with one
or more of the following prefixes/suffixes
1. Rain/Snow clouds Nimbo/Nimbus the
prefix/suffix given to any rain or snow
cloud. Ex Nimbostratus a stratus storm
cloud Cumulonimbus a
cumulus storm cloud
2. Altitude Cirro High level clouds (above
7000m). Made of ice crystals Ex
Cirrocumulus a high-level cumulus cloud
Cirrostratus a high-level stratus
cloud Alto Mid-level clouds (clouds between
2000m and 7000m) Ex Altocumulus a
mid-level cumulus cloud Altostratus a
mid-level stratus cloud Strato/Stratus Nearly
all low level clouds are stratus clouds. Ex
stratus, stratocumulus, nimbostratus
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High Level Clouds
Prefix Cirro (Cirrus) means clouds made of ice
crystals. Since all high altitude clouds are
made of ice, they all have the prefix Cirro.
Click images to enlarge
Cirrus the most common of the high cloud group.
They are composed of ice crystals and look like
long, thin wispy clouds. They predict fair
weather.
Cirrocumulus small rounded puffs that usually
appear in long rows, usually white but sometimes
gray. Can look like the scales of a fish. They
generally appear in winter and indicate fair but
cold weather.
Cirrostratus sheet-like thin clouds that
usually cover the entire sky. Usually come 24
hours before a rain or snow storm.
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Cirrus cloud
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Cirrocumulus cloud
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Cirrostratus cloud
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Middle Clouds
Prefix Alto means mid-level clouds. They
exist between 2000m and 7000m above the ground,
with a mix of ice crystals and water droplets.
They usually predict bad weather coming.
Click images to enlarge
Altocumulus they are grayish white, with one
part of the cloud darker than the other. They
usually form in groups and are generally about
1km thick. If you see altocumulus clouds on a
warm, humid morning, expect thundershowers to
come.
Altostratus sheet-like thin clouds that cover
the entire sky with a gray or blue-gray
appearance. They usually form ahead of storms
that have continuous rain or snow
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Altocumulus cloud
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Altostratus cloud
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Low Clouds
Nearly all low clouds are some form of stratus
cloud. Low clouds consist of water droplets
Click images to enlarge
Stratus they are uniform gray in colour and
cover all of the sky. They look like fog. They
are associated with light mist and drizzle.
Stratocumulus they are low, lumpy and gray.
They only give light precipitation or drizzle.
Nimbostratus they are dark gray with a ragged
base, and are usually associated with continual
rain or snow. They cover the whole sky.
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Stratus clouds
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Stratocumulus
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Nimbostratus
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Clouds with Vertical Growth
Some cloud types can exist at any altitude, or
are large enough to pass through multiple
altitudes. They consist of a mixture of water
droplets (at lower altitudes) and ice crystals
(at higher altitudes).
Click images to enlarge
Cumulus puffy white clouds that look like
floating cotton balls. Have sharp outlines and a
flat base. Cumulus clouds can be associated with
good or bad weather. Small cumulus clouds mean
good weather larger cumulus clouds are in the
last stage of becoming stormy cumulonimbus clouds.
Cumulonimbus can grow as large as 10km high,
and have an anvil-shaped top. Associated with
heavy rain, snow, hail, lightning and tornadoes.
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Cumulus
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Cumulonimbus
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Try and classify the following clouds
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Altostratus
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Cirrostratus
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Cirrus
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Cumulus
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Altostratus
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Stratocumulus
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Cirrus
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Cumulonimbus
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Cumulus
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Nimbostratus
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Cumulus
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Stratocumulus
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Nimbostratus
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Stratus
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Cumulonimbus