Term | Definition |
Cumulus | Often called “fair-weather” clouds, cumulus clouds
are common over land on sunny days, when the sun
heats the land creating thermal convection currents
Each thermal is distinct, and, consequently, each
cumulus cloud is a distinct puff |
Cumulonimbus | Ready supply of warm, moist air, which
rises at speeds of up to 25-70 mph
Tropospheric winds need to increase
considerably with height to encourage it to
slant forward
The atmosphere around the cloud needs to
be “unstable” no temp. inversions here |
Stratus | Stratus clouds are the lowest forming and are often
called fog or mists when they are earth-bound
Stratus clouds are formed when
a large air mass cools at the
same time (e.g. – a warm air
parcel drifts into or above a
cooler region) |
Stratocumulus | Similar to cumulus clouds in form and composition,
stratocumulus clouds are textured and puffy, but also
joined into a semi-continuous layer
Stratocumulus clouds usually form from cumulus or
stratus clouds |
Altocumulus | Since altocumulus clouds are high in the sky, they are
generally above the influence of thermals, and form
very differently from cumulus and stratocumulus clouds,
who share similar names. |
Altostratus | Below 6,500 ft. it’s stratus
Between 6,500 and 23,000 ft. it’s altostratus
Boring! – but being so high up, they do make for nice
sunsets. |
Nimbostratus | The nimbostratus cloud has no species or varieties.
It is a thick, wet blanket with a ragged base caused by
the continual precipitation |
Cirrus | Cirrus clouds are the highest of all clouds and are
composed entirely of ice crystals
Cirrus clouds are precipitating clouds although the
ice crystals evaporate high above the earth’s surface
crystals caught in 100 150 mph winds create
wisps cloud |
Cirrocumulus | Cirrocumulus clouds are usually a transitional phase
between cirrus and cirrostratus clouds.
Large numbers of cirrocumulus clouds may indicate
poor weather is approaching. |
Cirrostratus | Cirrostratus clouds are difficult to spot and appear as
a pale, milky lightening of the sky.
Cirrostratus clouds never block out the sun
completely, but rather produce a variety of optical
effects. |