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This is a photograph of altocumulus clouds.
Click on image for full size
Courtesy of UCAR Digital Image Library

Altocumulus

Altocumulus clouds are part of the Middle Cloud group. They are grayish-white with one part of the cloud darker than the other. Altocumulus clouds usually form in groups.

Altocumulus clouds are about as wide as your thumb when you hold up your hand at arm's length to look at the cloud.

If you see altocumulus clouds on a warm sticky morning, then expect thunderstorms by late afternoon.


Last modified September 25, 2007 by Becca Hatheway.

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