Cirrocumulus (Cc)


Source: http://www.met.utah.edu/galleries/home_page_images/cirro_cu2.JPG/photo_view

Level: 23,000 ft. and up

Composition: Ice

Typical Conditions: Generally fair weather. Most common under cold, stable regimes in the winter.

Appearance: Very small "blobs" of white in the upper-levels. Although they can easily be confused with altocumulus, the main distinguishing features are the very small size of each individual cloud and the lack of any shadow from cirrocumulus. "Mackerel sky" is a slang term used for when cirrocumulus cover a large portion of the sky, referring to the fish-scale-like appearance of the clouds.