Abbreviation Cu
Family C (humilis, mediocris, etc.) or D (congestus, pyrocumulus, etc.)
Genus Cumulus
Occurrence Worldwide
Altitude 600-9000m
Formation weak to moderate convection, sometimes enhanced by atmospheric instability
Precipitation Some varieties can produce showers and storms
Potential Hazards Moderate turbulence at cloud level; may develop into cumulonimbus cumulogenitus

Cumulus (Cu; Latin for heap) is a common genus of cloud which is formed by the rising of pockets of warm air and which has the appearance of a heap of cloud rising from a horizontal base. The cumulus cloud is commonly described as looking like a cotton ball or as "fluffy". Most of the time, cumulus clouds have a solid white colour, but some "towering" cumulus clouds can become dark. Cumulus congestus clouds can develop into cumulonimbus calvus clouds and thence into cumulonimbus incus clouds; each of these is capable of generating storms and showers.

Cumulus clouds were first described by Luke Howard in 1802 as "convex or conical heaps, increasing upwards from a horizontal base - wool bag clouds".


Cumulus arcus
Cumulus castellanus
Cumulus congestus
Cumulus fractus
Cumulus humilis
Cumulus mediocris
Cumulus pannus
Cumulus praecipitatio
Cumulus radiatus
Cumulus tuba
Cumulus velum
Orographic cumulus

Associated Formations Edit