Description Stratocumulus and differences with similar clouds

Grey or whitish, or both grey and whitish, patch, sheet or layer of cloud which almost always has dark parts, composed of tessellations, rounded masses, rolls, etc., which are non-fibrous (except for Virga) and which may or may not be merged; most of the regularly arranged small elements have an apparent width of more than five degrees.

Stratocumulus may, in extremely cold weather, produce abundant Virga of ice crystals, sometimes accompanied by a Halo; it is then nevertheless distinguishable from Cirrostratus by the fact that it still shows some evidence of the presence of rounded masses, rolls, etc. Furthermore, the opacity of Stratocumulus is greater than that of Cirrostratus.

Stratocumulus may sometimes he confused with Altocumulus having dark parts. If most of the regularly arranged elements, when observed at an angle of more than 30 degrees above the horizon, have an apparent width of more than five degrees, the cloud is Stratocumulus.

The differentiation of Stratocumulus from Altostratus, Nimbostratus and Stratus is based on the fact that Stratocumulus shows evidence of the presence of elements, merged or separate. Furthermore, in contrast with Altostratus which often has a fibrous appearance, Stratocumulus always appears non-fibrous, except at extremely low temperatures. In addition to the above criteria, the character of the precipitation and the nature of its particles sometimes provide a clue to the identity of the cloud; any precipitation from Stratocumulus is always of weak intensity.

Stratocumulus differs from Cumulus in that its elements usually occur in groups or patches and generally have flat tops; if however, Stratocumulus tops are in the form of domes, they rise, unlike those of Cumulus, from merged bases.