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This is a photograph of altostratus clouds.
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Courtesy of Keith G. Diem. Used by permission.

Altostratus

Altostratus clouds belong to the Middle Cloud group. An altostratus cloud usually covers the whole sky. The cloud looks gray or blue-gray. The sun or moon may shine through an altostratus cloud, but will look like a watery or fuzzy blob.

An altostratus cloud usually forms ahead of storms that have a lot of rain or snow. Sometimes, rain will fall from an altostratus cloud. If the rain hits the ground, then the cloud is called a nimbostratus cloud.


Last modified September 25, 2007 by Becca Hatheway.

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