Cirrocumulus clouds are high-altitude clouds that mainly occur between 16,000 and 40,000 feet. Like most cumulus clouds, these clouds indicate a vertical and upward transference of atmospheric conditions. Unlike other cirrus clouds, cirrocumulus composition includes super-cooled liquid water droplets. Ice crystals are also present, and usually, the ice crystals cause the droplets in the cloud to freeze rapidly, transforming the cirrocumulus into cirrostratus. This process can also produce ice or snow precipitation. Thus cirrocumulus clouds are typically short-lived. The term cirrocumulus refers to each individual cloud, but more commonly, the title is used when describing the entire patch of clouds. When it is used in this manner, each unit is referred to separately as a “cloudlet”.
A cirrocumulus is normally a small, white patch without a gray shadow. It occurs in sheets or patches along with other cirrocumulus. They are commonly organized in rows like other cumulus, but since they are so small, these patches take on a finer appearance, sometimes referred to as “herringbone” or “mackerel”. These clouds, because they carry water droplets, do not have the unique veil-like look of other high-level clouds, and consists of separate cloudlets that resemble altocumulus.
There are several differences in cirrocumulus and altocumulus, although both cloud types can occasionally occur together with no clear distinguishable differences between them. Cirrocumulus usually occur at higher altitudes than altocumulus; they are colder as well. Cirrocumulus never cast self-shadows and are translucent to a degree. They also are seen with other cirrus clouds in the sky, and usually transform noticeably into these other types of cirrus.