Stratocumulus floccus (Sc flo) | Cloud Atlas - MeteoAcademy.com - Online Course for Meteorology and Weather

Description

The name "floccus" (Latin: flake, tuft) describes the fluffy, tuft-like appearance of this cloud species. Stratocumulus floccus appears as individual, irregularly shaped cloud shreds or tufts with a frayed, often rounded top and a ragged, sometimes disintegrating base. This cloud form develops when local convection occurs within a moist layer, but the cloud elements dissolve rapidly before they can merge into a continuous layer. Stratocumulus floccus is a relatively rare species within the stratocumulus genus and is sometimes confused with Altocumulus floccus, but differs by its lower base and larger individual cloud elements.

Identification Features

Fluffy, tuft-like cloud elements at low altitude

Irregular, swollen tops with a frayed base

Individual cloud tufts that do not merge into a closed layer

Significantly larger elements than in Altocumulus floccus

Cloud base typically below 2,000 meters

Fallstreaks (virga) may be visible below the cloud elements

Often arranged in groups, but with distinct gaps in between

Appearance resembles torn cotton wool tufts in the sky

Occurrence by genus

Highlighted: all genera with which floccus occurs.

Cloud species and the genera with which they most commonly occur

Genus →Species ↓	Ci	Cc	Cs	Ac	As	Ns	Sc	St	Cu	Cb
fibratus (fib)
uncinus (unc)
spissatus (spi)
castellanus (cas)
floccus (flo)
stratiformis (str)
nebulosus (neb)
lenticularis (len)
volutus (vol)
fractus (fra)
humilis (hum)
mediocris (med)
congestus (con)
calvus (cal)
capillatus (cap)

Source: WMO International Cloud Atlas (2017)

Meteorological Significance

Stratocumulus floccus indicates moisture and slight instability in the lower troposphere, where convection is not strong enough to form more substantial clouds. The appearance of this cloud form can signal increasing atmospheric destabilization and may thus serve as a precursor to convective developments. When fallstreaks are present, this indicates precipitation forming within the cloud, though the drops typically evaporate before reaching the ground. In combination with other cloud types, Stratocumulus floccus can indicate an approaching change in weather, particularly if the clouds are increasing in depth. When occurring in isolation, significant precipitation is generally not to be expected.

Genera:	Altocumulus Ac Altostratus As Cirrocumulus Cc Cirrostratus Cs Cirrus Ci Cumulonimbus Cb Cumulus Cu Nimbostratus Ns Stratocumulus Sc Stratus St
Species:	castellanus Sc casfloccus Sc flolenticularis Sc len stratiformis Sc str volutus Sc vol

Stratocumulus floccus

Description

Identification Features

Occurrence by genus

Meteorological Significance

Facts