Cirrocumulus
Cc
Cirrocumulus
© Wetterkurs.ch
Description
Cirrocumulus (lat. cirrus = curl of hair, cumulus = heap) is a high cloud genus consisting of many small, white cloud globules or platelets arranged regularly in groups or rows. These thin cloud fields are found at great altitude and consist predominantly of ice crystals, though they may also contain supercooled water droplets. Their characteristic arrangement creates the so-called "mackerel sky" pattern. The individual elements have an apparent width of less than one degree (approximately the width of a little finger held at arm's length). Cirrocumulus is among the rarer cloud genera and is often only briefly visible before transforming into cirrus or cirrostratus.
Identification Features
- Very small, regularly arranged white cloud elements at great altitude
- Individual elements have an apparent width of less than 1 degree (little finger held at arm's length)
- Often in the form of fields, rows, or wave-like patterns (so-called mackerel sky pattern)
- White and without self-shadowing, as they are very thin
- Noticeably smaller elements than altocumulus (risk of confusion)
- Can produce iridescence or a corona around the sun or moon
- Often only temporarily visible, rapidly transforming into other cloud forms
- No halo phenomenon (unlike cirrostratus)
Species of this genus
Highlighted: all species that occur with Cirrocumulus.
Meteorological Significance
Cirrocumulus frequently forms through wave-like air movements or weak convection at great altitude, indicating moisture and instability in the upper troposphere. The appearance of cirrocumulus can signal an approaching warm front or a general change in weather, particularly when the cloud fields increase and become denser. In combination with other high and mid-level clouds, cirrocumulus can herald precipitation within the next 12 to 24 hours. When occurring in isolation and in small fields, however, cirrocumulus generally has no immediate significance for weather development. In tropical regions, extensive cirrocumulus can occasionally indicate the approach of a tropical cyclone.
Facts
- WMO-Code
- Cc
- Height layer
- High clouds
- Typical height
- 5.0 - 13.0 km
- Genus
- CIRROCUMULUS