Stratocumulus castellanus cloud

Mid-level cloud that indicates unstable air

Stratocumulus castellanus
Stratocumulus castellanus, with various turrets of very small size and one of a larger size
Abbreviation	Sc cas
Symbol
Genus	Stratocumulus
Species	Castellanus
Altitude	Above 2,000 m (Above 6,560 ft)
Appearance	small turrets
Precipitation	Virga, and sometimes light rain

Stratocumulus castellanus or Stratocumulus castellatus^[1] is a type of stratocumulus cloud, castellanus is derived from Latin, meaning 'of a castle' This type of cloud appears as cumuliform turrets vertically rising from a common horizontal cloud base, these turrets are taller than they are wide^[2]

This type of cloud indicates an increasingly unstable atmosphere,^[3] and seeing this type of cloud in the morning usually means that there is a possibility of thunderstorms forming later in the afternoon^[4] In the right conditions, these clouds can grow into cumulus congestus clouds, and sometimes, into cumulonimbus clouds^[5]

References

^ "Appendix 3 - History of cloud nomenclature".
^ "Stratocumulus castellanus (Sc cas) | International Cloud Atlas". 2021-09-19. Archived from the original on 2021-09-19. Retrieved 2021-11-02.
^ World Meteorological Organization (1975). Manual on the observation of clouds and other meteors. Internet Archive. Geneva : Secretariat of the World Meteorological Organization. ISBN 978-92-63-10407-6.
^ "Castellanus Clouds: Rising Towers, Turrets | WhatsThisCloud". 2021-11-02. Archived from the original on 2021-11-02. Retrieved 2021-11-02.
^ "Stratocumulus castellanus (Sc cas) | International Cloud Atlas". 2021-09-19. Archived from the original on 2021-09-19. Retrieved 2021-11-02.

Cloud genera and selected species, supplementary features, and other airborne hydrometeors - WMO Latin terminology except where indicated

Mesospheric

Extreme-level
80–85 km

Noctilucent (NLC) Polar mesospheric clouds	Noctilucent type I veils Noctilucent type II bands Noctilucent type III billows Noctilucent type IV whirls

Stratospheric

Very high-level
15–30 km

Nacreous polar stratospheric clouds (PSC)	Cirriform nacreous Lenticular nacreous
Nitric acid and water polar stratospheric clouds (PSC)	No differentiated sub-types; tends to resemble cirrostratus

Tropospheric

High-level
3–18 km

Cirrus (Ci)

Species	Cirrus castellanus (Ci cas) Cirrus fibratus (Ci fib) Cirrus floccus (Ci flo) Cirrus spissatus (Ci spa) Cirrus uncinus (Ci unc)
Ci-only varieties	Cirrus intortus (Ci in) Cirrus vertebratus (Ci ve)

Cirrocumulus (Cc)

Species	Cirrocumulus castellanus (Cc cas) Cirrocumulus floccus (Cc flo) Cirrocumulus lenticularis (Cc len) Cirrocumulus stratiformis (Cc str)

Cirrostratus (Cs)

Species	Cirrostratus fibratus (Cs fib) Cirrostratus nebulosus (Cs neb)

High-level-only
mutatus cloud

Mutatus non-height specific (see below)

Medium-level
2–8 km

Altocumulus (Ac)

Species	Altocumulus castellanus (Ac cas) Altocumulus floccus (Ac flo) Altocumulus lenticularis (Ac len) Altocumulus stratiformis (Ac str) Altocumulus volutus (Ac vol)

Altostratus (As)

Altostratus undulatus

Nimbostratus (Ns)
Multi-level

Varieties	Nimbostratus virga (Ns vir)

Low-level
0–2 km

Cumulonimbus (Cb)
Towering vertical

Species	Cumulonimbus calvus (Cb cal) Cumulonimbus capillatus (Cb cap)
Cb-only supplementary features	Cumulonimbus cauda ((cau) Tail cloud) Cumulonimbus incus (inc) Cumulonimbus murus ((mur) Wall cloud)
Cb-only accessories and other	Cumulonimbus flumen ((Cb flu) Beaver tail) Overshooting top Hot tower

Cumulus (Cu)
Variable vertical extent

Species	Fractus Cumulus humilis (Cu hum) Cumulus mediocris (Cu med) (Cumulus congestus (Cu con) (Cumulus castellanus (unofficial alternative name for Cu con)) (ICAO term for Cu con and "Cu cas" is Towering cumulus [Tcu]))
Other	Horseshoe Trade wind cumulus

Stratus (St)

Species	Stratus fractus (St fra) Stratus nebulosus (St neb)
St-only genitus cloud and other	Stratus silvagenitus (St sil) Fog (Fg) Surface level

Stratocumulus (Sc)

Species	Stratocumulus castellanus (Sc cas) Stratocumulus floccus (Sc flo) Stratocumulus lenticularis (Sc len) Stratocumulus stratiformis (Sc str) Stratocumulus Undulatus Stratocumulus volutus (Sc vol)

Low-level-only
supplementary features

Arcus ((arc) Shelf)
Tuba ((tub) Funnel cloud)

Low-level-only
accessory cloud and other

Pileus (pil)
Velum (vel)
Pannus (pan)
Other- Actinoform cloud (Stratocumulus)

Non-height
specific

Varieties	Duplicatus (du) Lacunosus (la) Opacus (op) Perlucidus (pe) Radiatus (ra) Translucidus (tr) Undulatus (un)
Supplementary features	Asperitas (asp) Cavum (cav) Fluctus (flu) Mamma (mam) Praecipitatio (pra) Virga (vir)
Mother clouds and human-made clouds	(Mother cloud)+genitus (e.g. cumulogenitus (cugen) (Mother cloud)+mutatus (e.g. cumulomutatus (cumut) Homogenitus (hogen) Homomutatus (homut)