This is a photograph of altostratus clouds.
Click on image for full size
Courtesy of Keith G. Diem. Used by permission.
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.
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