Anatomy
of a Cloud
The white or gray color of clouds is actually the light reflected by
tons of little droplets of water and crystals of ice that are so small,
they are able to stay in the atmosphere and not fall to Earth. A cloud
forms when humid air that contains water vapor is cooled. At cooler temperatures,
air is unable to hold as much water as at warm temperatures, so some
of the water is forced out of the air. It forms a droplet around a particle
of dust in the atmosphere or, if cold enough, turns into ice crystals.
When the number of droplets becomes so dense that the cloud looks gray
or black in color, it will probably produce precipitation. The cloud
becomes darker in color because the water droplets are so dense that
no light gets through.
Types of Clouds
Clouds exist in a variety of types. Each type of cloud forms under
certain circumstances of temperature, pressure, and humidity. Visit
our cloud
gallery to explore the variety of clouds that appear in our sky.
The variety of cloud types
not only makes them enjoyable to watch but, in fact, they can provide
useful clues to the weather ahead. As you
walk out your front door each day, take a quick survey of cloud types
to prepare
for the day’s weather. In general, small, white, thin cirrus
clouds usually mean that snow or rain is unlikely, while large, dark
cumulonimbus
clouds mean that a storm is looming.