Home / Glossary / Species Terms

Species Terms

Calvus: Cumulonimbus in which at least some protuberances of the upper part are beginning to lose their cumuliform outlines but in which no cirriform parts can be distinguished. Protuberances and sproutings tend to form a whitish mass, with more or less vertical striations.

Capillatus: Cumulonimbus characterized by the presence, mostly in its upper portion, of distinct cirriform parts of clearly fibrous or striated structure, frequently having the form of an anvil, a plume or a vast, more or less disorderly mass of hair. Cumulonimbus capillatus is usually accompanied by a shower or by a thunderstorm, often with squalls and sometimes with hail; it frequently produces very well-defined virga.

Castellanus: Clouds which present, in at least some portion of their upper part, cumuliform protuberances in the form of turrets which generally give the clouds a crenelated appearance. The turrets, some of which are taller than they are wide, are connected by a common base and seem to be arranged in lines.

Congestus: Cumulus clouds which are markedly sprouting and are often of great vertical extent. Their bulging upper part requently resembles a cauliflower.

Fibratus: Detached clouds or a thin cloud veil, consisting of nearly sraight or more or less irregularly curved filaments which do not terminate in hooks or tufts.

Floccus: A species in which each cloud unit is a small tuft with a cumuliform appearance, the lower part of which is more or less ragged and often accompanied by virga.

Fractus: clouds in the form of irregular shreds, which have a clearly ragged appearance.

Humilis: Cumulus clouds of only a slight vertical extent. They generally appear flattened.

Lenticularis: Clouds having the shape of lenses or almonds, often very elongated and usually with well-defined outlines; they occasionally show irisation. Such clouds appear most often in cloud formations of orographic origin, but may also occur in regions without marked orography.

Mediocris: Cumulus clouds of moderate vertical extent, the tops of which show fairly small protuberances.

Nebulosus: A cloud like a nebulous veil or layer, showing no distinct details.

Spissatus: Cirrus of sufficient optical thickness to appear greyish when viewed towards the sun.

Stratiformis: Clouds spread out in an extensive horizontal sheet or layer.