Cirrocumulus floccus
Cc flo
Cirrocumulus floccus
© Wetterkurs.ch
Description
The name "floccus" (Latin: tuft) describes small, fluffy cloudlets with a slightly ragged or rounded shape, reminiscent of cotton wool tufts. Cirrocumulus floccus consists of tiny, individually standing cloud puffs at high altitude, composed exclusively of ice crystals or supercooled water droplets. Each of these tufts has a slightly turreted top and may display virga (fallstreaks) at its base. The elements are distinctly smaller than a thumb's width at arm's length and often appear distributed across the sky in irregular groups. Their presence indicates moisture zones and instability in the upper troposphere.
Identification Features
- Very small, fluffy cloudlets at high altitude (typically above 6,000 m)
- Individual elements have a slightly swollen, billowy top
- Apparent width of individual elements is less than 1° (smaller than a finger at arm's length)
- Often accompanied by fine fallstreaks (virga) at the base
- No continuous cloud layer, but rather scattered tufts
- Distinguished from Altocumulus floccus by their smaller size and greater altitude
- Whitish, delicate appearance with no significant shading on the underside
Occurrence by genus
Highlighted: all genera with which floccus occurs.
Meteorological Significance
Cirrocumulus floccus indicates instability and increased moisture in the upper troposphere. Its appearance can be an early sign of approaching frontal disturbances, particularly when the cloud cover increases in density and extent. The fallstreaks frequently associated with the tufts indicate sublimation of ice crystals in lower, drier air layers. In combination with other high or mid-level clouds, Cirrocumulus floccus can signal a deterioration in weather within the next 12 to 24 hours. When it appears in isolation and transiently, it generally has no immediate effect on surface weather.
Facts
- WMO-Code
- Cc flo
- Height layer
- High clouds
- Typical height
- 6.0 - 12.0 km
- Genus
- CIRROCUMULUS