The system of classifying clouds into various types bases itself the height of the cloud base and on the appearance of the cloud as seen by an observer from the ground. Clouds that form in high altitudes usually evolve out of cirrus clouds, and have a prefix 'cirr-' in their names.
Cirrocumulus clouds are one such high altitude clouds that form at all latitudes, and usually in the winter.
Cirrocumulus clouds (abbreviated "Cc") are usually white and sometimes gray in color, and resemble small rounded puffs. They do not have the distinctive veil-like or fibrous look of other high altitude clouds, never cast self-shadows and are translucent to certain degree.
There are many species and varieties of the Cirrocumulus (Cc) clouds based on their size, shape, and form of the elements.
Cc Castellanus are tufted and turreted cloudlets
Cc floccus consist of tiny tufts of cloud, with rounded heads and ragged bases. They usually appear in large numbers spreading across the sky. The term cirrocumulus usually refers to each individual cloud, but also refers to an entire patch of cirrocumulus. When used in this way, each cirrocumulus element is the patch gets the name "cloudlet".
Cirrocumulus dominates the sky only on rare occasions. However, when it does, extensive horizontal sheets of small cloudlets that cover a substantial part of the sky reflect the red or yellow light of the sun low on the horizon, and the result is a spectacular sunset stretching over hundreds of miles. This type of cirrocumulus, known as the Cc
Stratiforms species is the most attractive of cloud types.
At times, the formation would be disrupted by large clear holes in the sheet of the cirrocumuls. This happens when some of the ice crystals that make up the cloud vaporize. Such types of clouds belong to the species Cc Lacunosus
When there is more than one layer of cirrocumulus clouds at slightly different layers, the species is Cc Duplicatus.
Another dramatic form that the cirrocumulus takes is appearing as fine ripples stretching across the sky in rows. These form because of high-level atmospheric waves, caused by wind sheers, and on such occasions the sky represents scales of a fish. Such patterns are called Cc undulates, and at such times the sky is referred to as "mackerel" or "herringbone".
If the ripples in the clouds are lense-shaped and have sharp edges, they are called Cc lenticularis.
Cirrocumulus clouds appear similar to altocumulus clouds, with the difference being the former occurring at higher levels and the latter at lower levels. Since cirrocumulus occurs at higher altitudes, these clouds appear smaller than altocumulus clouds, and are colder. Again,
cirrocumulus has no shading, which altocumulus usually has. At times, these two clouds occur together, and when that does, one cannot easily distinguish between the two.
HOW IT FORMS
Cirrocumulus clouds usually form at 16,000 to 18,000 feet (5000 to 13000 meters). When the hot air in the atmosphere gently warms the cirrus or cirrostratus clouds from below they rise to reach higher altitudes, where temperatures are -40 degree centigrade. The moist air saturates, freezes, and forms the type of clouds known as Cirrocumulus.
Since Cirrocumulus clouds form at high altitudes, they comprise entirely of ice crystals and super cooled water drops.
IMPACT ON WEATHER
Cirrocumulus clouds indicate fair, but cold weather. However, by itself they do not have any major meteorological significance. In tropical regions, they may indicate an approaching hurricane, but this is not a conclusive indicator.
The Cc castellanus type of clouds is a good indicator for shallow upper air convection and might be a good indicator for an afternoon or evening thunder. Cc undulatus that appear from west and thicken into
altocumulus clouds herald an approaching warm front and possibly rain within the next 18 to 36 hours.
Cirrocumulus clouds are short-lived. The ice crystals that make up this cloud cause the remaining super cooled water drops to freeze rapidly, thereby transforming the cirrocumulus back into cirrostratus. This process also produces precipitation in the form of a virga, consisting of ice or snow.