Cirrocumulus cloud

Cirrocumulus cloud
Cirrocumulus floccus
AbbreviationCc[1]
GenusCirro- (curl)
-cumulus (heaped)
Species
  • Castellanus
  • Flocus
  • Lenticularis
  • Stratiformis
Variety
  • Lacunosus
  • Undulatus
Altitude6,096–15,000 m
(20,000–49,000 ft)
ClassificationFamily A (High-level)
AppearanceSmall, flakey, and white high-altitude cumulus patches.
PrecipitationOccasionally virga.[2] May form ahead of a frontal system, especially together with other cirriform clouds meaning rain in around 10 hours.

Cirrocumulus is one of the three main genus types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus.[3] They usually occur at an altitude of 5 to 12 km (16,000 to 39,000 ft), however they can occur as low as 10,000 ft (3.0 km) in the arctic and weather reporting standards such as the Canadian MANOBS suggests heights of 29,000 ft (8.8 km) in summer and 26,000 ft (7.9 km) in winter.[4] Like lower-altitude cumuliform and stratocumuliform clouds, cirrocumulus signifies convection. Unlike other high-altitude tropospheric clouds like cirrus and cirrostratus, cirrocumulus includes a small amount of liquid water droplets, although these are in a supercooled state. Ice crystals are the predominant component, and typically, the ice crystals cause the supercooled water drops in the cloud to rapidly freeze, transforming the cirrocumulus into cirrostratus. This process can also produce precipitation in the form of a virga consisting of ice or snow. Thus, cirrocumulus clouds are usually short-lived.[5] They usually only form as part of a short-lived transitional phase within an area of cirrus clouds and can also form briefly as a result of the breaking up of part of a cumulonimbus anvil.

Properly, the term cirrocumulus refers to each cloud, but is typically also used to refer to an entire patch of cirrocumulus. When used in this way, each cirrocumulus element is referred to as a "cloudlet".[6]

  1. ^ Cite error: The named reference ahrens-120 was invoked but never defined (see the help page).
  2. ^ "Cirrocumulus Clouds" (PDF). Cloud Microphysics Webpage. Georgia Institute of Technology. Archived from the original (PDF) on 12 May 2011. Retrieved 6 February 2011.
  3. ^ Funk, Ted. "Cloud Classifications and Characteristics" (PDF). The Science Corner. NOAA. Retrieved 6 February 2011.
  4. ^ "Manual of Surface Weather Observation Standards (MANOBS) 8th Edition, Amendment 2". 2 December 2021.
  5. ^ Pretor-Pinney, Gavin (2009). The Cloud Collector's Handbook. Sceptre. ISBN 978-0-340-91943-9., p.21
  6. ^ "Cirrocumulus – Meteorology/Climate". Integration and Application Network. University of Maryland Center for Environmental Science. Retrieved 6 February 2011.