This is a photograph of a cumulonimbus cloud. Notice how the top of the cloud is shaped like an anvil.
Click on image for full size
Courtesy of UCAR Digital Image Library

Cumulonimbus

Cumulonimbus (weather symbol - Cb) clouds belong to the Clouds with Vertical Growth group. They are generally known as thunderstorm clouds. A cumulonimbus cloud can grow to such heights that it actually reaches the tropopause. At this height, high winds will flatten the top of the cloud out into an anvil-like shape. Cumulonimbus clouds are associated with heavy rain, snow, hail, lightning, and tornadoes.


Last modified September 25, 2007 by Becca Hatheway.

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