The list of cloud types groups all genera as ''high'' (cirro-, cirrus), ''middle'' (alto-), ''multi-level'' (nimbo-, cumulo-, cumulus), and ''low'' (strato-, stratus). These groupings are determined by the altitude level or levels in the

troposphere The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the Atmosphere, planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the ...

at which each of the various cloud types is normally found. Small

cumulus Cumulus clouds are clouds that have flat bases and are often described as puffy, cotton-like, or fluffy in appearance. Their name derives from the Latin , meaning "heap" or "pile". Cumulus clouds are low-level clouds, generally less than in a ...

are commonly grouped with the low clouds because they do not show significant vertical extent. Of the multi-level genus-types, those with the greatest convective activity are often grouped separately as ''towering vertical''. The genus types all have Latin names. The genera are also grouped into five physical forms. These are, in approximate ascending order of instability or convective activity: ''stratiform'' sheets; ''cirriform'' wisps and patches; ''stratocumuliform'' patches, rolls, and ripples; ''cumuliform'' heaps, and ''cumulonimbiform'' towers that often have complex structures. Most genera are divided into ''species'' with Latin names, some of which are common to more than one genus. Most genera and species can be subdivided into ''varieties'', also with Latin names, some of which are common to more than one genus or species. The essentials of the modern nomenclature system for tropospheric

clouds In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles, suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may c ...

were proposed by

Luke Howard Luke Howard (28 November 1772 – 21 March 1864) was a British manufacturing chemist and an amateur meteorologist with broad interests in science. His lasting contribution to science is a nomenclature system for clouds, which he proposed in ...

, a

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies. * British national identity, the characteristics of British people and culture ...

manufacturing

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...

and an

amateur An amateur () is generally considered a person who pursues an avocation independent from their source of income. Amateurs and their pursuits are also described as popular, informal, autodidacticism, self-taught, user-generated, do it yourself, DI ...

meteorologist A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmosphere of Earth, atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists ...

with broad interests in

science Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

, in an 1802 presentation to the Askesian Society. Very low stratiform clouds that touch the Earth's surface are given the common names ''fog'' and ''mist'', which are not included with the Latin nomenclature of clouds that form aloft in the troposphere. Above the troposphere, stratospheric and mesospheric clouds have their own classifications with common names for the major types and alpha-numeric nomenclature for the subtypes. They are characterized by altitude as ''very high level'' (polar stratospheric) and ''extreme level'' (polar mesospheric). Three of the five physical forms in the troposphere are also seen at these higher levels, stratiform, cirriform, and stratocumuliform, although the tops of very large cumulonimbiform clouds can penetrate the lower stratosphere.

Cloud identification and classification: Order of listed types

In section two of this page (Classification of major types), height ranges are sorted in approximate descending order of altitude expressed in general terms. On the cross-classification table, forms and genus types (including some genus sub-types) are shown from left to right in approximate ascending order of instability. In sections three to five, terrestrial clouds are listed in descending order of the altitude range of each atmospheric layer in which clouds can form: * mesospheric layer; * stratospheric layer; *

tropospheric The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the planetary s ...

layer. ** Within the troposphere, the cloud levels are listed in descending order of altitude range. *** Non-vertical genus types (including some genus sub-types) are sorted into approximate descending order of altitude of the cloud bases. *** Vertical or multi-level genera and genus sub-types can be based in the low or middle levels and are therefore placed between the non-vertical low and mid-level genus types and sub-types. These thick clouds are listed in approximate descending order of altitude of the cloud tops. **** The species associated with each genus type are listed in approximate ascending order of instability where applicable. **** The constituent varieties and associated supplementary features and mother clouds for each genus or species are arranged in approximate order of frequency of occurrence. ****A count of basic tropospheric variants that result from the division and subdivision of genus types into species and varieties is shown as a number in parentheses from V-1 (variant 1) through V-93 after each variety, after

nimbostratus A nimbostratus cloud is a multilevel, amorphous, nearly uniform, and often dark-grey cloud that usually produces continuous rain, snow, or sleet, but no lightning or thunder.cloud In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles, suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may ...

types in the general lists and the mother clouds in the applicable classification table are sorted in alphabetical order except where noted. The species table shows these types sorted from left to right in approximate ascending order of the convective instability of each species. The table for supplementary features has them arranged in approximate descending order of frequency of occurrence. In section seven, extraterrestrial clouds can be found in the atmospheres of other

planets A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the te ...

in the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

and beyond. The planets with clouds are listed (not numbered) in order of their distance from the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

, and the clouds on each planet are in approximate descending order of altitude.

Cloud cross-classification throughout the homosphere

The table that follows is very broad in scope much like the cloud genera template near the bottom of the article and upon which this table is partly based. There are some variations in styles of nomenclature between the classification scheme used for the troposphere (strict Latin except for surface based aerosols) and the higher levels of the

homosphere The homosphere is the layer of an atmosphere where the bulk gases are homogeneously mixed due to turbulent mixing or eddy diffusion. The bulk composition of the air is mostly uniform so the concentrations of molecules are the same throughout the ho ...

(common terms, some informally derived from Latin). However, the schemes presented here share a cross-classification of physical forms and altitude levels to derive the 10 tropospheric genera, the fog and mist that forms at surface level, and several additional major types above the troposphere. The

genus includes four species that indicate vertical size which can affect the altitude levels.

Mesospheric cloud identification and classification

Clouds In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles, suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may c ...

that form in the

mesosphere The mesosphere (; ) is the third layer of the atmosphere, directly above the stratosphere and directly below the thermosphere. In the mesosphere, temperature decreases as altitude increases. This characteristic is used to define limits: it be ...

come in a variety of forms such as veils, bands, and billows, but are not given Latin names based on these characteristics. These clouds are the highest in the atmosphere and are given the Latin-derived name noctilucent which refers to their illumination during deep

twilight Twilight is daylight illumination produced by diffuse sky radiation when the Sun is below the horizon as sunlight from the upper atmosphere is scattered in a way that illuminates both the Earth's lower atmosphere and also the Earth's surf ...

rather than their physical forms. They are sub-classified alpha-numerically and with common terms according to specific details of their physical structures.

Extreme-level stratiform, stratocumuliform, and cirriform

Noctilucent cloud Noctilucent clouds (NLCs), or night shining clouds, are tenuous cloud-like phenomena in the upper atmosphere of Earth. When viewed from space, they are called polar mesospheric clouds (PMCs), detectable as a diffuse scattering layer of water ice ...

s are thin clouds that come in a variety of forms based from about and occasionally seen in deep twilight after sunset and before sunrise. ;Type 1 : Veils, very tenuous stratiform; resembles cirrostratus or poorly defined cirrus. ;Type 2 : Long stratocumuliform bands, often in parallel groups or interwoven at small angles. More widely spaced than cirrocumulus bands. :;2A : Bands with diffuse, blurred edges. :;2B : Bands with sharply defined edges. ;Type 3: Billows. Clearly spaced, fibrous cirriform, roughly parallel short streaks. :;3A : Short, straight, narrow streaks. :;3B : Wave-like structures with undulations. ;Type 4 : Whirls. Partial (or, more rarely, complete) cirriform rings with dark centers. :;4A : Whirls possessing a small angular radius of curvature, sometimes resembling light ripples on a water surface. :;4B : Simple curve of medium angular radius with one or more streaks. :;4C : Whirls with large-scale ring structures.

Stratospheric cloud identification and classification

Polar stratospheric clouds form at very high altitudes in

polar Polar may refer to: Geography * Geographical pole, either of the two points on Earth where its axis of rotation intersects its surface ** Polar climate, the climate common in polar regions ** Polar regions of Earth, locations within the polar circ ...

regions of the stratosphere. Those that show

mother-of-pearl Nacre ( , ), also known as mother-of-pearl, is an organicinorganic composite material produced by some molluscs as an inner shell layer. It is also the material of which pearls are composed. It is strong, resilient, and iridescent. Nacre is ...

color Color (or colour in English in the Commonwealth of Nations, Commonwealth English; American and British English spelling differences#-our, -or, see spelling differences) is the visual perception based on the electromagnetic spectrum. Though co ...

s are given the name ''nacreous''.

Very high-level stratiform

;Nitric acid and water polar stratospheric : Sometimes known as type 1, a thin sheet-like cloud resembling cirrostratus or haze. Contains supercooled

nitric acid Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most com ...

and water droplets; sometimes also contains supercooled

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

in ternary solution.

Very high-level cirriform and stratocumuliform

; Nacreous polar stratospheric cloud (mother of pearl): Sometimes known as type 2, a thin usually cirriform or lenticular (stratocumuliform) looking cloud based from about and seen most often between

sunset Sunset (or sundown) is the disappearance of the Sun at the end of the Sun path, below the horizon of the Earth (or any other astronomical object in the Solar System) due to its Earth's rotation, rotation. As viewed from everywhere on Earth, it ...

and

sunrise Sunrise (or sunup) is the moment when the upper rim of the Sun appears on the horizon in the morning, at the start of the Sun path. The term can also refer to the entire process of the solar disk crossing the horizon. Terminology Although the S ...

. Consists of ice crystals only.

Troposphere cloud identification and classification

Tropospheric clouds are divided into physical forms defined by structure, and levels defined by altitude range. These divisions are cross-classified to produce ten basic genus-types. They have Latin names as authorized by the

World Meteorological Organization The World Meteorological Organization (WMO) is a List of specialized agencies of the United Nations, specialized agency of the United Nations responsible for promoting international cooperation on atmospheric science, climatology, hydrology an ...

(WMO) that indicate physical structure, altitude or étage, and process of formation.

High-level cirriform, stratocumuliform, and stratiform

High clouds form in the highest and coldest region of the troposphere from about 5 to 12 km (16,500 to 40,000 ft) in temperate latitudes. At this altitude water almost always freezes so high clouds are generally composed of

ice crystal Ice crystals are solid water (known as ice) in symmetrical shapes including hexagonal columns, hexagonal plates, and dendritic crystals. Ice crystals are responsible for various atmospheric optical displays and cloud formations. Formation ...

s or supercooled water droplets.

Genus cirrus

Abbreviation: Ci Cirriform clouds tend to be wispy and are mostly transparent or translucent. Isolated cirrus do not bring

rain Rain is a form of precipitation where water drop (liquid), droplets that have condensation, condensed from Water vapor#In Earth's atmosphere, atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is res ...

; however, large amounts of cirrus can indicate an approaching

storm A storm is any disturbed state of the natural environment or the atmosphere of an astronomical body. It may be marked by significant disruptions to normal conditions such as strong wind, tornadoes, hail, thunder and lightning (a thunderstor ...

system eventually followed by fair

weather Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloud cover, cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmo ...

. There are several variations of clouds of the cirrus genus based on species and varieties:

=Species

; Cirrus fibratus (V-1): High clouds having the traditional "mare's tail" appearance. These clouds are long, fibrous, and curved, with no tufts or curls at the ends. ; Cirrus uncinus (V-2): Filaments with up-turned hooks or curls. ; Cirrus spissatus (V-3): Dense and opaque or mostly opaque patches. ; Cirrus castellanus (V-4): A series of dense lumps, or "towers", connected by a thinner base. ; Cirrus floccus (V-5): Elements which take on a rounded appearance on the top, with the lower part appearing ragged.

=Varieties

= ; Opacity-based: None; always translucent except species spissatus which is inherently opaque. ; Fibratus pattern-based: :; Cirrus fibratus intortus (V-6): Irregularly curved or tangled filaments. :; Cirrus fibratus vertebratus (V-7): Elements arranged in the manner of a

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

skeleton A skeleton is the structural frame that supports the body of most animals. There are several types of skeletons, including the exoskeleton, which is a rigid outer shell that holds up an organism's shape; the endoskeleton, a rigid internal fra ...

. ; Pattern-based variety radiatus: Large horizontal bands that appear to converge at the

horizon The horizon is the apparent curve that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This curve divides all viewing directions based on whethe ...

; normally associated with fibratus and uncinus species. :; Cirrus fibratus radiatus (V-8): :; Cirrus uncinus radiatus (V-9): ; Pattern-based variety duplicatus: Sheets at different layers of the upper troposphere, which may be connected at one or more points; normally associated with fibratus and uncinus species. :; Cirrus fibratus duplicatus (V-10): :; Cirrus uncinus duplicatus (V-11): ; Spissatus, castellanus, or floccus: Varieties are not commonly associated.

=Supplementary features

= ; Precipitation-based: Not associated with cirrus. ; Cloud-based: :; Mamma: Bubble-like downward protuberances; mostly seen with species castellanus. ; Genitus mother clouds: :; Cirrus cirrocumulogenitus: :; Cirrus altocumulogenitus: :; Cirrus cumulonimbogenitus: :; Cirrus homogenitus: Cirrus formed by spreading of aircraft contrails. ; Mutatus mother cloud: :; Cirrus cirrostratomutatus: :; Cirrus homomutatus: Cirrus formed by the complete transformation of cirrus homogenitus.

Genus cirrocumulus

Abbreviation: Cc. High-level stratocumuliform clouds of the genus

cirrocumulus Cirrocumulus is one of the three main genus types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus. They usually occur at an altitude of , however they can occur as low as in the arctic and weather reporting sta ...

form when moist air at high tropospheric altitude reaches saturation, creating ice crystals or supercooled water droplets. Limited convective instability at the cloud level gives the cloud a rolled or rippled appearance. Despite the lack of a ''strato-'' prefix, layered cirrocumulus is physically a high stratocumuliform genus.Burroughs, William James; Crowder, Bob (January 2007). ''Weather'', p.216. Fog City Press, San Francisco. .

=High stratocumuliform species

= ;

Cirrocumulus stratiformis Cirrocumulus stratiformis is a type of cirrocumulus cloud. The name ''cirrocumulus stratiformis'' is derived from Latin, meaning "stretched out". Cirrocumulus stratiformis occurs as very small cirrocumulus clouds that cover a large part of the sky ...

(V-12): Sheets or relatively flat patches of cirrocumulus. ; Cirrocumulus lenticularis (V-13): Lenticular, or

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

-shaped high cloud. ; Cirrocumulus castellanus (V-14): Cirrocumulus layer with "towers", or

turret Turret may refer to: * Turret (architecture), a small tower that projects above the wall of a building * Gun turret, a mechanism of a projectile-firing weapon * Optical microscope#Objective turret (revolver or revolving nose piece), Objective turre ...

s joined at the bases. ; Cirrocumulus floccus (V-15): Very small white heaps with ragged bases and rounded tops.

=Varieties

= ; Opacity-based varieties: None (always translucent). ; Pattern-based varieties: :; Undulatus: Cirrocumulus with an undulating base; normally associated with stratiformis and lenticularis species. ::; Stratocumuliform undulatus (V-16): ::; Cirrocumulus stratiformis undulatus (V-17): ::; Cirrocumulus lenticularis undulatus (V-18): :; Lacunosus: Cirrocumulus with large clear holes; normally associated with stratiformis and castellanus species (also with cumuliform floccus species). ::; Stratocumuliform lacunosus: ::; Cirrocumulus stratiformis lacunosus (V-19): ::; Cirrocumulus castellanus lacunosus (V-20): ::; Cirrocumulus floccus lacunosus (V-21):

=Supplementary features

= ; Precipitation-based supplementary feature: :; Virga: Light

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. The main forms of precipitation include drizzle, rain, rain and snow mixed ("sleet" in Commonwe ...

that evaporates well above ground level; mostly seen with species stratiformis, castellanus, and floccus. ; Cloud-based supplementary feature: :; Mamma: Bubble-like downward protuberances; mostly seen with species castellanus. ; Genitus mother clouds: No genitus types. ; Mutatus mother clouds: :; Cirrocumulus cirromutatus :; Cirrocumulus cirrostratomutatus :; Cirrocumulus altocumulomutatus :; Cirrocumulus homomutatus: Results from the transformation of cirrus homogenitus.

Genus cirrostratus

Abbreviation: Cs Sun Halo Salinas Victoria Desert

Clouds of the genus

cirrostratus Cirrostratus () is a high-altitude, very thin, and generally uniform stratiform genus-type of cloud. It is composed of ice crystals, which are particles of frozen water. Cirrostratus is difficult to see and can produce halos. These optical e ...

consist of mostly continuous, wide sheets of cloud that covers a large area of the sky. It is formed when convectively stable moist air cools to saturation at high altitude, forming ice crystals.Burroughs, William James; Crowder, Bob (January 2007). ''Weather'', p.215. Fog City Press, San Francisco. . Frontal cirrostratus is a precursor to rain or

snow Snow consists of individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water througho ...

if it thickens into mid-level altostratus and eventually nimbostratus, as the

weather front A weather front is a boundary separating air masses for which several characteristics differ, such as air density, wind, temperature, and humidity. Disturbed and unstable weather due to these differences often arises along the boundary. For ins ...

moves closer to the observer.

=Species

= ;

Cirrostratus fibratus Cirrostratus fibratus or also called Cirrostratus filosus is a type of cirrostratus cloud. The name ''cirrostratus fibratus'' is derived from Latin, meaning "fibrous". Cirrostratus fibratus is one of the two most common forms that cirrostratus of ...

(V-22): Cirrostratus sheet with a fibrous appearance, but not as detached as cirrus. ;

Cirrostratus nebulosus Cirrostratus nebulosus is a type of high-level cirrostratus cloud. The name ''cirrostratus nebulosus'' is derived from Latin, the adjective ''nebulosus'' meaning "full of vapor, foggy, cloudy, dark". Cirrostratus nebulosus is one of the two most c ...

(V-23): Featureless, uniform sheet.

=Varieties

= ; Opacity-based varieties: None (always translucent) ; Fibratus pattern-based varieties: :; Cirrostratus fibratus duplicatus (V-24): Separate or semi-merged sheets with one layer slightly above the other. :; Cirrostratus fibratus undulatus (V-25): Undulating

wave In physics, mathematics, engineering, and related fields, a wave is a propagating dynamic disturbance (change from List of types of equilibrium, equilibrium) of one or more quantities. ''Periodic waves'' oscillate repeatedly about an equilibrium ...

s. ; Varieties are not commonly associated with Cs species nebulosus.

=Supplementary features

= : Supplementary features/accessory clouds: Not associated with cirrostratus. ; Genitus mother clouds: :; Cirrostratus cirrocumulogenitus: :; Cirrostratus cumulonimbogenitus: ; Mutatus mother clouds: :; Cirrostratus cirromutatus: :; Cirrostratus cirrocumulomutatus: :; Cirrostratus altostratomutatus: :; Cirrostratus homomutatus: Results from the transformation of cirrus homogenitus.

Mid-level stratocumuliform and stratiform

Middle cloud forms from 2 to 7 km (6,500–23,000 ft) in temperate latitudes, and may be composed of water droplets or ice crystals depending on the temperature profile at that altitude range.

Genus altocumulus

Abbreviation: Ac Mid-level stratocumuliform clouds of the genus

altocumulus Altocumulus () is a middle-altitude cloud genus that belongs mainly to the physical category, characterized by globular masses or rolls in layers or patchesthe individual elements being larger and darker than those of cirrocumulus and smaller t ...

are not always associated with a weather front but can still bring precipitation, usually in the form of

virga A virga, also called a dry storm, is an observable streak or shaft of precipitation that evaporates or sublimates before reaching the ground. A shaft of precipitation that does not evaporate before reaching the ground is known in meteoro ...

which does not reach the ground. Layered forms of altocumulus are generally an indicator of limited convective instability, and are therefore mainly stratocumuliform in structure.

=Mid-level stratocumuliform species

= ;

Altocumulus stratiformis Altocumulus stratiformis is the most common species of the Altocumulus Altocumulus () is a middle-altitude cloud genus that belongs mainly to the physical category, characterized by globular masses or rolls in layers or patchesthe individual ...

: Always dividable into opacity-based varieties. Sheets or relatively flat patches of altocumulus. ; Altocumulus lenticularis (V-26): Lens-shaped middle cloud. Includes informal variant altocumulus Kelvin–Helmholtz cloud, lenticular spiral indicative of severe

turbulence In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to laminar flow, which occurs when a fluid flows in parallel layers with no disruption between ...

. ; Altocumulus volutus (V-27): Elongated, tube shaped, horizontal stratocumuliform cloud. ;

Altocumulus castellanus In meteorology, Altocumulus castellanus or Altocumulus castellatus (ACCAS) is a cloud type named for its tower-like projections that billow upwards from the base of the cloud. The base of the cloud can form as low as 2,000 metres (6,500 feet), or ...

(V-28): Turreted layer cloud. ;

Altocumulus floccus Altocumulus () is a middle-altitude cloud genus that belongs mainly to the physical category, characterized by globular masses or rolls in layers or patchesthe individual elements being larger and darker than those of cirrocumulus and smaller ...

(V-29): Tufted stratocumuliform clouds with ragged bases.

=Varieties

= ; Opacity-based varieties: :; Altocumulus stratiformis translucidus (V-30): Translucent altocumulus through which the

sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

or moon can be seen. :; Altocumulus stratiformis perlucidus (V-31): Opaque middle clouds with translucent breaks. :; Altocumulus stratiformis opacus (V-32): Opaque altocumulus that obscures the sun or

moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

. ; Pattern-based varieties: :; Radiatus: Rows of altocumulus that appear to converge at the horizon; normally associated with stratiformis species. ::; Altocumulus stratiformis translucidus radiatus (V-33): ::; Altocumulus stratiformis perlucidus radiatus (V-34): ::; Altocumulus stratiformis opacus radiatus (V-35): :; Duplicatus: Altocumulus in closely spaced layers, one above the other; normally associated with stratiformis and lenticularis species. ::; Altocumulus stratiformis translucidus duplicatus (V-36): ::; Altocumulus stratiformis perlucidus duplicatus (V-37): ::; Altocumulus stratiformis opacus duplicatus (V-38): ::; Altocumulus lenticularis duplicatus (V-39): :; Undulatus: Altocumulus with wavy undulating base; normally associated with stratiformis and lenticularis species. ::; Altocumulus stratiformis translucidus undulatus (V-40): ::; Altocumulus stratiformis perlucidus undulatus (V-41): ::; Altocumulus stratiformis opacus undulatus (V-42): ::; Altocumulus lenticularis undulatus (V-43): :; Lacunosus: Altocumulus with circular holes caused by localized

downdraft In meteorology, an updraft (British English: ''up-draught'') is a small-scale current of rising air, often within a cloud. Overview Vertical drafts, known as updrafts or downdrafts, are localized regions of warm or cool air that move vertically ...

s; normally associated with stratiformis and castellanus species (also with cumuliform floccus species). ::; Altocumulus stratiformis translucidus lacunosus (V-44): ::; Altocumulus stratiformis perlucidus lacunosus (V-45): ::; Altocumulus stratiformis opacus lacunosus (V-46): ::; Altocumulus castellanus lacunosus (V-47): ::; Altocumulus floccus lacunosus (V-48):

=Supplementary features

= ; Precipitation-based supplementary feature: :; Virga: Altocumulus producing precipitation that evaporates before reaching the ground; usually associated with species stratiformis, castellanus, and floccus. ; Cloud-based supplementary feature: :; Mamma: Altocumulus (usually species castellanus) with downward facing bubble-like protuberances caused by localized downdrafts within the cloud. ; Genitus mother clouds: :; Altocumulus cumulogenitus: :; Altocumulus cumulonimbogenitus: ; Mutatus mother clouds: :; Altocumulus cirrocumulomutatus: :; Altocumulus altostratomutatus: :; Altocumulus nimbostratomutatus: :; Altocumulus stratocumulomutatus:

Genus altostratus

Abbreviation: As Stratiform clouds of the genus

altostratus Altostratus is a middle-altitude cloud genus made up of water droplets, ice crystals, or a mixture of the two. Altostratus clouds are formed when large masses of warm, moist air rise, causing water vapor to condense. Altostratus clouds are usual ...

form when a large convectively stable

air mass In meteorology, an air mass is a volume of air defined by its temperature and humidity. Air masses cover many hundreds or thousands of square miles, and adapt to the characteristics of the surface below them. They are classified according to ...

is lifted to condensation in the middle level of the troposphere, usually along a frontal system. Altostratus can bring light rain or snow. If the precipitation becomes continuous, it may thicken into nimbostratus which can bring precipitation of moderate to heavy intensity.

=Species

= No differentiated species (always nebulous).

=Varieties

= ; Opacity-based varieties: :; Altostratus translucidus (V-49): Altostratus through which the sun can be seen. :; Altostratus opacus (V-50): Altostratus that completely blocks out the sun. ; Pattern-based variety radiatus: Bands that appear to converge at the horizon. :; Altostratus translucidus radiatus (V-51): :; Altostratus opacus radiatus (V-52): ; Pattern-based variety duplicatus: Altostratus in closely spaced layers, one above the other. :; Altostratus translucidus duplicatus (V-53): :; Altostratus opacus duplicatus (V-54): ; Pattern-based variety undulatus: Altostratus with wavy undulating base. :; Altostratus translucidus undulatus (V-55): :; Altostratus opacus undulatus (V-56):

=Supplementary features

= ; Precipitation-based supplementary features: :; Virga: Accompanied by precipitation that evaporates before reaching the ground. Seen mostly with opacus varieties. :; Praecipitatio: Produces precipitation that reaches the ground; associated with opacus varieties. ; Cloud-based supplementary feature: :; Mamma: Altostratus with downward facing bubble-like protuberances caused by localized downdrafts within the cloud. ; Accessory cloud: Seen mostly with opacus varieties :; Pannus: Accompanied by ragged lower layer of fractus species clouds forming in precipitation. ; Genitus mother clouds: :; Altostratus altocumulogenitus: :; Altostratus cumulonimbogenitus: ; Mutatus mother clouds: :; Altostratus cirrostratomutatus: :; Altostratus nimbostratomutatus:

Towering vertical cumulonimbiform and cumuliform (low to mid-level cloud base)

Clouds with upward-growing vertical development usually form below , but can be based as high as in temperate climates, and often much higher in arid regions.

Genus cumulonimbus: Towering vertical

Abbreviation: Cb Clouds of the genus cumulonimbus have very-dark-gray-to-nearly-black flat bases and very high tops that can penetrate the

tropopause The tropopause is the atmospheric boundary that demarcates the lowest two layers of the atmosphere of Earth – the troposphere and stratosphere – which occurs approximately above the equatorial regions, and approximately above the polar regi ...

. They develop from cumulus when the

is convectively highly unstable. They generally produce

thunderstorms A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are som ...

showers A shower is a place in which a person bathes under a spray of typically warm or hot water. Indoors, there is a drain in the floor. Most showers are set up to have adjustable temperature, spray pressure and showerhead nozzle angle. The si ...

, and sometimes

hail Hail is a form of solid Precipitation (meteorology), precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailsto ...

, strong

outflow Outflow may refer to: *Capital outflow, the capital leaving a particular economy *Bipolar outflow, in astronomy, two continuous flows of gas from the poles of a star * Outflow (hydrology), the discharge of a lake or other reservoir system *Outflow ...

wind Wind is the natural movement of atmosphere of Earth, air or other gases relative to a planetary surface, planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heatin ...

s, and/or

tornadoes A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the ...

at ground level.

=Species

= ;

Cumulonimbus calvus Cumulonimbus calvus is a moderately tall cumulonimbus cloud that is capable of precipitation but has not yet reached the tropopause, which is the height of stratospheric stability at which cumulonimbus forms into cumulonimbus capillatus (fibrous- ...

(V-57): Cumulonimbus with high domed top. ; Cumulonimbus capillatus (V-58): Towering vertical cloud with high cirriform top.

=Varieties

= No varieties (always opaque and does not form in patterns visible from surface level).

=Supplementary features

= ; Precipitation-based supplementary features: Associated with calvus and capillatus species. :; Virga: Precipitation that evaporates before reaching the ground. :; Praecipitatio: Precipitation that reaches the ground. ; Cloud-based supplementary features: :;

Incus The ''incus'' (: incudes) or anvil in the ear is one of three small bones (ossicles) in the middle ear. The incus receives vibrations from the malleus, to which it is connected laterally, and transmits these to the stapes medially. The incus i ...

(species capillatus only): Cumulonimbus with flat anvil-like cirriform top caused by wind shear where the rising air currents hit the inversion layer at the tropopause. :; Mamma: Also sometimes called Mammatus, consisting of bubble-like protrusions on the underside caused by localized downdrafts. :; Arcus (including

roll Roll may refer to: Physics and engineering * Rolling, a motion of two objects with respect to each-other such that the two stay in contact without sliding * Roll angle (or roll rotation), one of the 3 angular degrees of freedom of any stiff bo ...

and shelf clouds): Low, horizontal cloud formation associated with the leading edge of thunderstorm outflow. :; Tuba: Column hanging from the cloud base which can develop into a funnel cloud or tornado. ; Accessory clouds: Seen with species and capillatus except where noted. :; Pannus: Accompanied by a lower layer of fractus species cloud forming in precipitation. :; Pileus (species calvus only): Small cap-like cloud over parent cumulonimbus. :; Velum: A thin horizontal sheet that forms around the middle of a cumulonimbus. ; Genitus mother clouds: :; Cumulonimbus altocumulogenitus: :; Cumulonimbus altostratogenitus: :; Cumulonimbus nimbostratogenitus: :; Cumulonimbus stratocumulogenitus: :; Cumulonimbus flammagenitus: Formed by large-scale fires or volcanic eruptions. ; Mutatus mother cloud: :; Cumulonimbus cumulomutatus:

Genus cumulus: Towering vertical

Abbreviations: Cu con (''cumulus congestus'') or Tcu (''towering cumulus'')

=Species

= ;

Cumulus congestus Cumulus congestus or towering cumulus clouds are a species of cumulus that can be based in the low- to middle-height ranges. They achieve considerable vertical development in areas of deep, moist convection. They are an intermediate stage between ...

(V-59): These large cumulus clouds have flat dark grey bases and very tall tower-like formations with tops mostly in the high level of the troposphere. The

International Civil Aviation Organization The International Civil Aviation Organization (ICAO ) is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international sch ...

(ICAO) designates this species as towering cumulus (Tcu).

=Varieties

= ; Opacity-based varieties: None (always opaque). ; Pattern-based variety: None (not generally discerned with highly unstable cumulus congestus).

=Supplementary features

= ; Precipitation-based supplementary features: :; Virga: Accompanied by precipitation that evaporates before reaching the ground. :; Praecipitatio: Produces precipitation that reaches the ground. ; Cloud-based supplementary features: :; Mamma: Downward facing bubble-like protuberances caused by localized downdrafts within the cloud. :; Arcus (including

and

shelf cloud An arcus cloud is a low, horizontal cloud formation, usually appearing as an accessory cloud to a cumulonimbus. Roll clouds and shelf clouds are the two main types of arcus clouds. They most frequently form along the leading edge or gust fronts o ...

s): Low horizontal cloud formation associated with the leading edge of a thunderstorm outflow. :; Tuba: Column hanging from the cloud base which can develop into a small funnel cloud. ; Accessory clouds: :; Pannus: Accompanied by a lower layer of fractus species cloud forming in precipitation. :; Pileus: Small cap-like cloud over parent cumulus cloud. :; Velum: A thin horizontal sheet that forms around the middle of a cumulus cloud. ; Mother clouds: :; Cumulus congestus flammagenitus: :; Other genitus and mutatus types are the same as for small and moderate cumulus.

Multi-level stratiform and moderate vertical cumuliform (low to mid-level cloud base)

Genus nimbostratus: Multi-level

Abbreviation: Ns (V-60) Clouds of the genus

nimbostratus A nimbostratus cloud is a multilevel, amorphous, nearly uniform, and often dark-grey cloud that usually produces continuous rain, snow, or sleet, but no lightning or thunder. from altostratus cloud but tends to thicken into the lower levels during the occurrence of precipitation. The top of a nimbostratus deck is usually in the middle level of the troposphere.

Virga A virga, also called a dry storm, is an observable streak or shaft of precipitation that evaporates or sublimates before reaching the ground. A shaft of precipitation that does not evaporate before reaching the ground is known in meteoro ...

: Accompanied by precipitation that evaporates before reaching the ground. :; Praecipitatio: Produces precipitation that reaches the ground. ; Accessory cloud: :; Pannus: Nimbostratus with lower layer of fractus species cloud forming in precipitation. ; Genitus mother clouds :; Nimbostratus cumulogenitus: :; Nimbostratus cumulonimbogenitus: ; Mutatus mother clouds: :; Nimbostratus altostratomutatus: :; Nimbostratus altocumulomutatus: :; Nimbostratus stratocumulomutatus:

Genus cumulus: Moderate vertical

Abbreviation: Cu Moderate vertical cumulus is the product of free convective air mass instability. Continued upward growth suggests showers later in the day.

=Species

= ;

Cumulus mediocris Cumulus mediocris is a low to middle level cloud with some vertical extent (Family D1) of the genus cumulus, larger in vertical development than Cumulus humilis. It also may exhibit small protuberances from the top and may show the cauliflower fo ...

(V-61): Moderate vertical clouds with flat medium grey bases and higher tops than cumulus humilis.

=Varieties

= : Opacity-based varieties: None (always opaque) ; Pattern-based variety: :; Cumulus mediocris radiatus (V-62) (V-60); Moderate cumulus clouds arranged in parallel lines that appear to converge at the horizon.

=Supplementary features

= : Precipitation-based supplementary features: :; Virga: Accompanied by precipitation that evaporates before reaching the ground. :; Praecipitatio: Produces precipitation that reaches the ground. ; Cloud-based supplementary feature: :; Mamma: Downward facing bubble-like protuberances caused by localized downdrafts within the cloud. ; Accessory clouds: :; Pileus; Small cap-like cloud over parent cumulus cloud. :; Velum: A thin horizontal sheet that forms around the middle of a cumulus cloud. ; Mother clouds: Genitus and mutatus types are the same as for cumulus of little vertical extent.

Low-level stratocumuliform, cumuliform, and stratiform

Low cloud forms from near surface to ca. and are generally composed of water droplets.

Genus stratocumulus

Abbreviation: Sc Clouds of the genus

stratocumulus A stratocumulus cloud, occasionally called a cumulostratus, belongs to a genus-type of clouds characterized by large dark, rounded masses, usually in groups, lines, or waves, the individual elements being larger than those in altocumulus, and the ...

are lumpy, often forming in slightly unstable air, and they can produce very light rain or drizzle.

=Species

= ; Stratocumulus stratiformis: Always dividable into opacity-based varieties. Sheets or relatively flat patches of stratocumulus ; Stratocumulus lenticularis (V-63): Lens-shaped low cloud. ; Stratocumulus volutus (V-64): Elongated, low-level, tube shaped, horizontal stratocumuliform cloud. ; Stratocumulus floccus (V-65): Scattered or isolated stratocumulus tufts with domed tops and ragged bases. ; Stratocumulus castellanus (V-66): Layer of turreted stratocumulus cloud with tower-like formations protruding upwards.

=Varieties

= ; Stratocumuliform opacity-based varieties: :; Stratocumulus stratiformis translucidus (V-67): Thin translucent stratocumulus through which the sun or moon can be seen. :; Stratocumulus stratiformis perlucidus (V-68): Opaque low clouds with translucent breaks. :; Stratocumulus stratiformis opacus (V-69): Opaque stratocumulus clouds. ; Pattern-based variety radiatus: Stratocumulus arranged in parallel bands that appear to converge on the horizon; normally associated with stratiformis species. :; Stratocumulus stratiformis translucidus radiatus (V-70): :; Stratocumulus stratiformis perlucidus radiatus (V-71): :; Stratocumulus stratiformis opacus radiatus (V-72): ; Pattern-based variety duplicatus: Closely spaced layers of stratocumulus, one above the other; normally associated with stratiformis and lenticularis species. :; Stratocumulus stratiformis translucidus duplicatus (V-73): :; Stratocumulus stratiformis perlucidus duplicatus (V-74): :; Stratocumulus stratiformis opacus duplicatus (V-75): :; Stratocumulus lenticularis duplicatus (V-76): ; Pattern-based variety undulatus: Stratocumulus with wavy undulating base; normally associated with stratiformis and lenticularis species. :; Stratocumulus stratiformis translucidus undulatus (V-77): :; Stratocumulus stratiformis perlucidus undulatus (V-78): :; Stratocumulus stratiformis opacus undulatus (V-79): :; Stratocumulus lenticularis undulatus (V-80): ; Pattern-based variety lacunosus: Sc with circular holes caused by localized downdrafts; normally associated with stratiformis and castellanus species. :; Stratocumulus stratiformis translucidus lacunosus (V-81): :; Stratocumulus stratiformis perlucidus lacunosus (V-82): :; Stratocumulus stratiformis opacus lacunosus (V-83): :; Stratocumulus castellanus lacunosus (V-84): :; Stratocumulus floccus lacunosus (V-85):

=Supplementary features

= ; Precipitation-based supplementary features: Usually associated with species stratiformis and castellanus. :; Virga: Low cloud producing precipitation that evaporates before reaching the ground. :; Praecipitatio: Stratocumulus clouds producing precipitation that reaches the ground. ; Cloud-based supplementary feature: :; Mamma: Stratocumulus with bubble-like protrusions on the underside; usually associated with species castellanus. ; Genitus mother clouds: :; Stratocumulus cumulogenitus: Clouds CL4

:; Stratocumulus nimbostratogenitus: :; Stratocumulus cumulonimbogenitus: :; Stratocumulus altostratogenitus: ; Mutatus mother clouds: :; Stratocumulus nimbostratomutatus: :; Stratocumulus altocumulomutatus: :; Stratocumulus stratomutatus:

Genus cumulus (little vertical extent)

Abbreviation: Cu These are fair weather cumuliform clouds of limited convection that do not grow vertically. The vertical height from base to top is generally less than the width of the cloud base. They appear similar to stratocumulus but the elements are generally more detached and less wide at the base.

=Species

= ; Cumulus fractus (V-86): Ragged shreds of cumulus clouds. ;

Cumulus humilis Cumulus humilis are cumuliform clouds with little vertical extent, common in the summer, that are often referred to as "fair weather cumulus". If they develop into cumulus mediocris or cumulus congestus, thunderstorms could form later in the day ...

(V-87): "Fair weather clouds" with flat light grey bases and small white domed tops.

=Varieties

= ; Opacity-based varieties: None (always opaque except species fractus which is always translucent). ; Humilis pattern-based variety: :; Cumulus humilis radiatus (V-88): Small cumulus clouds arranged in parallel lines that appear to converge at the horizon.

= Supplementary features and accessory clouds

= Not commonly seen with cumulus fractus or humilis. ; Genitus mother clouds :; Cumulus stratocumulogenitus :; Cumulus homogenitus: Clouds formed by air-mass convection associated with contained industrial activity. ; Mutatus mother clouds :; Cumulus stratocumulomutatus :; Cumulus stratomutatus ;; Cumulus cataractagenitus: Generated by the spray from waterfalls.

Genus stratus

Abbreviation: St Clouds of the genus

stratus Stratus may refer to: Weather *Stratus cloud, a cloud type **Nimbostratus cloud, a cloud type **Stratocumulus cloud, a cloud type **Altostratus cloud, a cloud type ** Altostratus undulatus cloud, a cloud type **Cirrostratus cloud, a cloud type Mu ...

form in low horizontal layers having a ragged or uniform base. Ragged stratus often forms in precipitation while more uniform stratus forms in maritime or other moist stable air mass conditions. The latter often produces drizzle. Stratus that touches the Earth's surface is given the common name,

fog Fog is a visible aerosol consisting of tiny water droplets or ice crystals suspended in the air at or near the Earth's surface. Reprint from Fog can be considered a type of low-lying cloud usually resembling stratus and is heavily influenc ...

, rather than a Latin name that applies only to clouds that form and remain aloft in the troposphere.

=Species

= ; Stratus nebulosus: Uniform fog-like low cloud. ;

Stratus fractus Fractus clouds, also called fractostratus or fractocumulus, are small, ragged cloud fragments that are usually found under an ambient cloud base. They form or have broken off from a larger cloud, and are generally sheared by strong winds, givin ...

(V-89): Ragged shreds of stratus clouds usually under base of precipitation clouds.

=Varieties

= ; Nebulosus opacity-based varieties: :; Stratus nebulosus translucidus (V-90): Thin translucent stratus. :; Stratus nebulosus opacus (V-91): Opaque stratus that obscures the sun or moon. ; Pattern-based variety undulatus: Wavy undulating base. :; Stratus nebulosus translucidus undulatus (V-92) :; Stratus nebulosus opacus undulatus (V-93) ; Varieties are not commonly associated with St species fractus.

=Supplementary features

= ; Precipitation-based supplementary feature: :; Praecipitatio: Stratus (usually species nebulosus) producing precipitation. ; Accessory clouds: Not usually seen with stratus. ; Genitus mother clouds and other mother sources: :; Stratus nimbostratogenitus :; Stratus cumulogenitus :; Stratus cumulonimbogenitus :; Stratus cataractagenitus: Generated by the spray from waterfalls. :; Stratus silvagenitus: A stratus cloud that forms as water vapor is added to the air above a forest. :; Stratus homogenitus ; Mutatus mother cloud: :; Stratus stratocumulomutatus

Tropospheric cloud types with Latin etymologies where applicable

''Cloud types are sorted in alphabetical order except where noted''.

WMO genera

;

Altocumulus Altocumulus () is a middle-altitude cloud genus that belongs mainly to the physical category, characterized by globular masses or rolls in layers or patchesthe individual elements being larger and darker than those of cirrocumulus and smaller t ...

(''altus'' and ''cumulus''): Latin for "high heap": Applied to mid-level stratocumuliform. ;

Altostratus Altostratus is a middle-altitude cloud genus made up of water droplets, ice crystals, or a mixture of the two. Altostratus clouds are formed when large masses of warm, moist air rise, causing water vapor to condense. Altostratus clouds are usual ...

(''altus'' and ''stratus''): "High sheet": Applied to mid-level stratiform. ;

Cirrocumulus Cirrocumulus is one of the three main genus types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus. They usually occur at an altitude of , however they can occur as low as in the arctic and weather reporting sta ...

(''cirrus'' and ''cumulus''): "Hair-like heap": Applied to high-level stratocumuliform. ;

Cirrostratus Cirrostratus () is a high-altitude, very thin, and generally uniform stratiform genus-type of cloud. It is composed of ice crystals, which are particles of frozen water. Cirrostratus is difficult to see and can produce halos. These optical e ...

(''cirrus'' and ''stratus''): "Hair-like sheet": Applied to high-level stratiform. ; Cirrus: "Hair-like": Applied to high-level cirriform. ;

Cumulonimbus Cumulonimbus () is a dense, towering, vertical cloud, typically forming from water vapor condensing in the lower troposphere that builds upward carried by powerful buoyant air currents. Above the lower portions of the cumulonimbus the water va ...

(''cumulus'' and ''nimbus''): "Precipitation-bearing heap": Applied to vertical/multi-level cumulonimbiform. ;

Cumulus Cumulus clouds are clouds that have flat bases and are often described as puffy, cotton-like, or fluffy in appearance. Their name derives from the Latin , meaning "heap" or "pile". Cumulus clouds are low-level clouds, generally less than in a ...

: "Heap": Applied to low-level and vertical/multi-level cumuliform. ;

Nimbostratus A nimbostratus cloud is a multilevel, amorphous, nearly uniform, and often dark-grey cloud that usually produces continuous rain, snow, or sleet, but no lightning or thunder.Stratocumulus A stratocumulus cloud, occasionally called a cumulostratus, belongs to a genus-type of clouds characterized by large dark, rounded masses, usually in groups, lines, or waves, the individual elements being larger than those in altocumulus, and the ...

(''stratus'' and ''cumulus''): "Sheet-like heap": Applied to low-level stratocumuliform. ;

Stratus Stratus may refer to: Weather *Stratus cloud, a cloud type **Nimbostratus cloud, a cloud type **Stratocumulus cloud, a cloud type **Altostratus cloud, a cloud type ** Altostratus undulatus cloud, a cloud type **Cirrostratus cloud, a cloud type Mu ...

: "Sheet": Applied to low-level mostly shallow stratiform.

WMO species

; Castellanus (Cas): Latin for "castle-like": Applies to stratocumuliform (Sc cas, Ac cas, Cc cas) and dense cirriform (Ci cas) with a series of

shapes – indicates air mass instability. ; Congestus (Con): Latin for "congested": Applies to cumuliform (Cu con/Tcu) with great vertical development and heaped into

cauliflower Cauliflower is one of several vegetables cultivated from the species '' Brassica oleracea'' in the genus '' Brassica'', which is in the Brassicaceae (or mustard) family. Cauliflower usually grows with one main stem that carries a large, rou ...

shapes – indicates considerable air mass instability and strong upcurrents. ; Fibratus (Fib): "Fibrous": Cirriform (Ci fib) or high stratiform (Cs fib) in the form of filaments, can be straight or slightly curved; indicates strong, continuous upper winds. ; Floccus (Flo): "Tufted": Applies to stratocumuliform (Sc flo, Ac flo, Cc flo) and high cirriform (Ci flo); indicates some mid or high-level instability. ; Fractus (Fra): "Broken": Low stratiform (St fra) or cumuliform (Cu fra) with an irregular shredded appearance – forms in precipitation and/or gusty winds. ; Humilis (Hum): "Small": Applies to cumuliform (Cu hum) with little vertical extent; indicates relatively slight air mass instability. ; Lenticularis (Len): "Lens–like": Stratocumuliform (Sc len, Ac len, Cc len) having a lens-like appearance – formed by standing

s of wind passing over

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

s or hills. Wavecloud

; Mediocris (Med): "Medium-size": Cumuliform (Cu med) with moderate vertical extent; indicates moderate instability and upcurrents. ; Nebulosus (Neb): "Nebulous": Indistinct low and high stratiform (St neb, Cs neb) without features; indicates light wind if any and stable air mass. ; Spissatus (Spi): "Dense": Thick cirriform (Ci spi) with a grey appearance; indicates some upward movement of air in the upper troposphere. ; Stratiformis (Str): "Sheet-like": Horizontal cloud sheet of flattened stratocumuliform (Sc str, Ac str, Cc str); indicates very slight air mass instability. ; Uncinus (Unc): "Hook-like": Cirriform (Ci unc) with a hook shape at the top; indicates a nearby backside of a weather system. ; Volutus (Vol): "Rolled": Elongated, low or mid-level, tube shaped, stratocumuliform (Sc vol, Ac vol). The division of genus types into species is as shown in the following table. The genus types (including some cumulus sub-types) are arranged from top to bottom in the left column in approximate descending order of average overall altitude range. The species are sorted from left to right in approximate ascending order of instability or vertical extent of the forms to which each belongs: # Stratiform species, # Cirriform species, # Stratocumuliform species, # Cumuliform species, # Cumulonimbiform species. These ordinal instability numbers appear in each box where a particular genus has a particular species.

WMO varieties

; Opacity-based: :; Opacus: Latin for "Opaque". A thick sheet of stratiform or stratocumuliform cloud. :; Perlucidus: "Semi-transparent". Sheet of stratocumuliform cloud with small spaces between elements. :; Translucidus: "Translucent". Thin translucent patch or sheet of stratiform or stratocumuliform. ; Pattern-based: :; Duplicatus: Latin for "Double". Closely spaced often partly merged layers of cloud in one of several possible forms. :; Intortus: "Twisted". Curved and tangled cirriform. :; Lacunosus: "Full of holes". Thin stratocumuliform cloud distinguished by holes and ragged edges. :; Radiatus: "Radial". Clouds in one of several possible forms arranged in parallel lines that appear to converge at a central point near the horizon. :; Undulatus: "Wavy". Stratiform or stratocumuliform cloud displaying an undulating pattern. :; Vertebratus: "In the form of a back-bone". Cirriform arranged to look like the back-bone of a

. The following table shows the cloud varieties arranged across the top of the chart from left to right in approximate descending order of frequency of appearance. The genus types and some sub-types associated with each variety are sorted in the left column from top to bottom in approximate descending order of average overall altitude range. Where applicable, the genera and varieties are cross-classified to show the species normally associated with each combination of genus and variety. The exceptions comprise the following: Altostratus that have varieties but no species so the applicable boxes are marked without specific species names; cumulus congestus, a species that has its own altitude characteristic but no varieties; cumulonimbus that have species but no varieties, and nimbostratus that has no species or varieties. The boxes for genus and species combinations that have no varieties are left blank.

WMO supplementary features

; Precipitation-based supplementary features: :; Praecipitatio: Latin for "falling": Cloud whose precipitation reaches the ground. Downburst 1

: "Twig" or "branch": Cloud whose precipitation evaporates before reaching the ground. Cirrocumulus-virga-01

; Cloud-based supplementary features: :; Arcus: Latin for "arch" or "bow": Feature mostly attached to cumulus, thick with ragged edges. Roll Cloud 001

:; Asperitas: "Roughness": A highly disturbed and chaotic wave feature occasionally seen with a stratocumulus or altocumulus cloud. Clouds similar to roll clouds

:; Cavum: "Hole": Supercooled altocumulus or cirrocumulus distinguished by a hole with ragged edges and virga or wisps of cirrus. OKC-Fallstreak

:; Cauda: "Tail": A tail cloud that extends horizontally away from the murus cloud and is the result of air feeding into the storm. Wallcloudwithtailcloud

:; Fluctus: Crested wave-like stratocumulus, altocumulus, or cirrus cloud formed by wind-shear. Stratocumuluskelvinhelmholtz

:; Incus: "Anvil": Top part of a mature cumulonimbus cloud; anvil-shaped feature. Mammatus clouds in anvil cloud

:; Mammatus: WMO term ''mamma'': "Breast": A feature in the form of round pouches on under-surface of a cloud. Mammatussquawvalley

:; Murus: "Wall": Cumulonimbus wall cloud with a lowering rotating base that can portend tornadoes. Cumulonimbus 4

:; Tuba: "Funnel" or "tube": Feature in the form of a column hanging from the bottom of cumulus or cumulonimbus. F5 tornado funnel cloud Elie Manitoba 2007

; Accessory clouds: :; Pannus: Latin for "shredded cloth": A ragged or shredded accessory cloud that forms in precipitation below the main cloud. Nimbostratus pannus

:; Pileus: "Capped": A hood-shaped accessory cloud. Cap cloud in cumulonimbus

:; Velum: "A ship's sail": An accessory cloud in the form of a sail. Cb velum near beach

The supplementary features are associated with particular genera as follows. They are sorted from left to right in approximate decreasing order of frequency of occurrence for each of three categories. The genus types and some sub-types are arranged from top to bottom in approximate descending order of average overall altitude range. Each box is marked where a particular genus or sub-type has a particular supplementary feature.

Genitus mother clouds

; Altocumulogenitus: Formed by the partial transformation of altocumulus mother cloud. ; Altostratogenitus: Formed by the partial transformation of altostratus. ; Cirrogenitus: Partial transformation of cirrus. ; Cirrocumulogenitus: Partial transformation of cirrocumulus. ; Cirrostratogenitus: Partial transformation of cirrostratus. ; Cumulogenitus: Spreading out or partial transformation of cumulus. ; Cumulonimbogenitus: Spreading out or partial transformation of cumulonimbus. ; Nimbostratogenitus: Partial transformation of nimbostratus. ; Stratogenitus: Partial transformation of stratus. ; Stratocumulogenitus: Partial transformation of stratocumulus.

Other genitus clouds

; Cataractagenitus (cataracta-/pertaining to a river cataract): Formed from the mist at a waterfall, the downdraft caused from the cloud is counteracted by the ascending air displacement from the waterfall and may go on to form other types of clouds such as ''cumulus cataractagenitus''. ; Flammagenitus (flamma-/pertaining to fire): Formed by convection associated with large wildfires. ; Homogenitus (homo-/pertaining to humans): Formed as a result of human activities, particularly aircraft at high altitudes and heat-generating industrial activities at surface level. If a homogenitus cloud of one genus changes to another genus type, it is then termed a ''homomutatus'' cloud. ; Silvagenitus (silva-/pertaining to trees or forests): Formed by low-level condensation of water vapor released by vegetation, especially forest canopies.

Mutatus mother clouds

Nomenclature works the same way as for genitus mother clouds except for the ''mutatus'' suffix to indicate the ''complete'' rather than the partial transformation of the original cloud type. e.g. Altocumulomutatus – formed by the complete transformation of altocumulus mother cloud. The possible combinations of genera and mother clouds can be seen in this table. The genitus and mutatus clouds are each sorted from left to right in alphabetical order. The genus types and some sub-types are arranged from top to bottom in approximate descending order of average overall altitude range. Each box is marked where a particular genus or sub-type has a particular genitus or mutatus mother cloud.

Informal terms recently accepted for WMO classification with Latin nomenclature

; Aviaticus cloud: Persistent condensation trails (contrails) formed by ice crystals originating from water vapor emitted by aircraft

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...

s. Usually resembles cirrus; recognized as a WMO genitus cloud cirrus ''homogenitus'' (man-made). Further transformation into cirrus, cirrocumulus, or cirrostratus homomutatus is possible depending on atmospheric stability and wind shear. ; Fallstreak hole: Supercooled altocumulus or cirrocumulus distinguished by a hole with ragged edges and virga or wisps of cirrus. Accepted as a WMO supplementary feature to be named ''cavum'' (hole). ; Kelvin–Helmholtz cloud: Wavecloudsduval

Crested wave-like clouds formed by wind-shear instability that may occur at any altitude in the troposphere. Accepted as a WMO supplementary feature with the Latin name ''fluctus''. ;

Pyrocumulus A flammagenitus cloud, also known as a flammagenitus, pyrocumulus cloud, or fire cloud, is a dense cumuliform cloud associated with fire or volcanic eruptions. A flammagenitus is similar dynamically in some ways to a firestorm, and the two phe ...

and

Pyrocumulonimbus The cumulonimbus flammagenitus cloud (CbFg), also known as the pyrocumulonimbus cloud, is a type of cumulonimbus cloud that forms above a source of heat, such as a wildfire, nuclear explosion, or volcanic eruption, and may sometimes even exting ...

: Cumulus and cumulonimbus clouds formed by quickly generated ground heat; including forest fires, volcanic eruptions and low level nuclear detonation. Accepted as a WMO genitus cloud with the Latin name ''flammagenitus'', or ''homogenitus'' in the case of small cumulus formed by contained human activity. ; Roll cloud: Roll-Cloud-Racine

Elongated, low-level, tube shaped, horizontal formation not associated with a parent cloud. Accepted as a WMO stratocumulus or altocumulus species with the Latin name ''volutus''.

WMO and informal terms related to free-convective cloud types and storms

* Accessory cloud (WMO supplementary feature) – secondary cloud that is associated with but separate from a main cloud. *Anvil (WMO supplementary feature incus) – the anvil top of a cumulonimbus cloud. *Anvil dome (WMO supplementary feature incus) – the

overshooting top An overshooting top (or penetrating top) is a dome-like protrusion shooting out of the top of the anvil of a thunderstorm and into the lower stratosphere. When an overshooting top is present for 10 minutes or longer, it is a strong indication that ...

on a Cb that is often present on a

supercell A supercell is a thunderstorm characterized by the presence of a mesocyclone, a deep, persistently rotating updraft. Due to this, these storms are sometimes referred to as rotating thunderstorms. Of the four classifications of thunderstorms (su ...

. *Anvil rollover – (slang) circular protrusion attached to underside of anvil. Cumulonimbuscapillatus01

* Arcus cloud (WMO supplementary feature) – arch or a bow shape, attached to cumulus, thick with ragged edges. *Backsheared anvil – (slang) anvil that spreads upwind, indicative of extreme weather. *Clear slot or dry slot (informal term) – an evaporation of clouds as a

rear flank downdraft The rear flank downdraft (RFD) is a region of dry air wrapping around the back of a mesocyclone in a supercell thunderstorm. These areas of descending air are thought to be essential in the production of many supercellular tornadoes. Large hail ...

descends and dries out cloud and occludes around a

mesocyclone A mesocyclone is a meso-gamma mesoscale (or storm scale) region of rotation ( vortex), typically around in diameter, most often noticed on radar within thunderstorms. In the Northern Hemisphere, it is usually located in the right rear flank ( ...

. *Cloud tags (WMO species fractus) – ragged detached portions of cloud. *Collar cloud (WMO velum accessory cloud) – ring shape surrounding upper part of wall cloud. *Condensation funnel (WMO supplementary feature tuba) – the cloud of a

funnel cloud A funnel cloud is a funnel-shaped cloud of condensed water droplets, associated with a rotating column of wind and extending from the base of a cloud (usually a cumulonimbus or towering cumulus cloud) but not reaching the ground or a water su ...

aloft or a tornado. *

(WMO genus and species) – castle crenellation-shaped altocumulus clouds. *

(WMO genus) – heaped clouds. * Cumulus castellanus – (informal variation of WMO genus and species cumulus congestus) cumulus with tops shaped like castle crenellations. *

(WMO genus and species) – considerable vertical development and heaped into cauliflower shapes. * Cumulus fractus (WMO genus and species) – ragged detached portions of cumulus cloud. *

(WMO genus and species) – small, low, flattened cumulus, early development. *

(WMO genus and species) – medium-sized cumulus with bulges at the top. *Cumulus pileus (WMO genus and accessory cloud) – capped, hood-shaped cumulus cloud. *Cumulus praecipitatio (WMO genus and supplementary feature) – cumulus whose precipitation reaches the ground. *Cumulus radiatus (WMO genus and variety) – cumulus arranged in parallel lines that appear to converge near the horizon. Cumulusradiatus1

*Cumulus tuba (WMO genus and supplementary feature) – column hanging from the bottom of cumulus. *

(WMO genus) – heaped towering rain-bearing clouds that stretch to the upper levels of the troposphere. *

(WMO genus and species) – cumulonimbus with round tops like cumulus congestus. * Cumulonimbus capillatus (WMO genus and species) – Cb with cirriform top. *

Cumulonimbus incus A cumulonimbus incus (), also called an anvil cloud, is a cumulonimbus cloud that has reached the level of stratospheric stability and has formed the characteristic flat, anvil-shaped top. It signifies a thunderstorm in its mature stage, suc ...

(WMO genus and supplementary feature) – Cb capillatus with anvil top. *Cumulonimbus mamma (WMO genus and supplementary feature) – Cb with pouch-like protrusions that hang from under anvil or cloud base. *Cumulonimbus pannus (WMO genus and accessory cloud) – shredded sections attached to main Cb cloud. *Cumulonimbus pileus (WMO genus and accessory cloud) – capped, hood-shaped cloud above a cumulonimbus cloud. *Cumulonimbus praecipitatio (WMO genus and supplementary feature) – Cb whose precipitation reaches the ground. *Cumulonimbus tuba (WMO genus and supplementary feature) – column hanging from the bottom of cumulonimbus. *Debris cloud (informal term) – rotating "cloud" of debris found at base of

tornado A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the ...

. *

Funnel cloud A funnel cloud is a funnel-shaped cloud of condensed water droplets, associated with a rotating column of wind and extending from the base of a cloud (usually a cumulonimbus or towering cumulus cloud) but not reaching the ground or a water su ...

(WMO supplementary feature tuba) – rotating funnel of cloud hanging from under Cb, not making contact with ground. *Hail fog (informal term) – a shallow surface layer of

that sometimes forms in vicinity of deep

accumulation, can be very dense. * Hot tower (informal term) – a tropical cumulonimbus cloud that penetrates the

. *Inflow band (informal term) – a laminar band marking inflow to a Cb, can occur at lower or mid levels of the cloud. *Inverted cumulus (informal variation of WMO supplementary feature mamma) – cumulus which has transferred momentum from an exceptionally intense Cb tower and is convectively growing on the underside of an anvil. *Knuckles (informal variation of WMO supplementary feature mamma) – lumpy protrusion that hangs from edge or underside of anvil. *

Marine layer A marine layer is an air mass that develops over the surface of a large body of water, such as an ocean or large lake, in the presence of a Inversion (meteorology), temperature inversion. The inversion itself is usually initiated by the cooling ...

Overcast Overcast or overcast weather, as defined by the World Meteorological Organization, is the meteorological condition of clouds obscuring at least 95% of the sky. However, the total cloud cover must not be entirely due to obscuring phenomena near ...

and Pyrocumulonimbus– intense ground-heat cloud proposed for WMO classification (see above). *Rope – (slang) narrow, sometimes twisted funnel type cloud seen after a tornado dissipates. *Rope cloud (informal term) – A narrow, long, elongated line of cumulus clouds that sometimes develop at the leading edge of an advancing cold front that is often visible in satellite imagery. * Scud cloud (informal term for WMO species fractus) – ragged detached portions of cloud that usually form in precipitation. *

Sea of clouds A sea of clouds is an overcast layer of stratocumulus clouds, as viewed from above, with a relatively uniform top which shows undulations of very different lengths resembling waves on the sea. A sea of fog is formed from stratus clouds or fog ...

Shelf cloud An arcus cloud is a low, horizontal cloud formation, usually appearing as an accessory cloud to a cumulonimbus. Roll clouds and shelf clouds are the two main types of arcus clouds. They most frequently form along the leading edge or gust fronts o ...

(informal term for WMO supplementary feature arcus) – wedge-shaped cloud often attached to the underside of Cb. *Stratus fractus (WMO genus and species) – ragged detached portions of stratus cloud that usually form in precipitation (see also scud cloud). *Striations (informal term for WMO accessory cloud velum) – a groove or band of clouds encircling an updraft tower, indicative of rotation. *Tail cloud (informal term) – an area of condensation consisting of laminar band and cloud tags extending from a

wall cloud A wall cloud (murus or pedestal cloud) is a large, localized, persistent, and often abrupt lowering of cloud that develops beneath the surrounding base of a cumulonimbus cloud and from which tornadoes sometimes form. It is typically beneath the ...

towards a precipitation core. *Towering cumulus (TCu) -aviation term for WMO genus and species cumulus congestus, a large cumulus cloud with great vertical development, usually with a cauliflower-like appearance, but lacking the characteristic anvil of a Cb. *

Wall cloud A wall cloud (murus or pedestal cloud) is a large, localized, persistent, and often abrupt lowering of cloud that develops beneath the surrounding base of a cumulonimbus cloud and from which tornadoes sometimes form. It is typically beneath the ...

(informal term) – distinctive fairly large lowering of the rain-free base of a Cb, often rotating.

Other planets

Venus

Thick overcast clouds of

sulfur dioxide Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...

and

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

in three main layers at altitudes of 45 to 65 km that obscure the

planet A planet is a large, Hydrostatic equilibrium, rounded Astronomical object, astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets b ...

's surface and can produce virga. ; Stratiform: Overcast opaque clouds sheets. ; Stratocumuliform: Wave clouds with clear gaps through which lower stratiform layers may be seen. ; Cumuliform and cumulonimbiform: Embedded convective cells that can produce lightning.

Mars

Clouds resembling several terrestrial types can be seen over Mars and are believed to be composed of

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

ice Ice is water that is frozen into a solid state, typically forming at or below temperatures of 0 ° C, 32 ° F, or 273.15 K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally oc ...

. ; Extremely high cirriform: Noctilucent clouds are known to form near the poles at altitudes similar to or higher than the same type of clouds over Earth. ; High cirriform: Thin scattered wispy cloud resembling cirrus through which the planet's surface can be seen. ; High stratocumuliform: Thin scattered wave-cloud resembling cirrocumulus. ; Low stratocumuliform: Wave-cloud resembling stratocumulus, especially as a polar cap cloud over the winter pole which is mostly composed of suspended frozen carbon dioxide. ; Surface-based: Morning fog of water and/or

commonly forms in low areas of the planet.

Jupiter and Saturn

Cloud decks in parallel bands of latitude at and below the

alternately composed of

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

crystals and

ammonium Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleu ...

hydrosulfate. ; Cirriform: Bands of cloud resembling cirrus located mainly in the highest of three main layers that cover Jupiter. ; Stratiform and stratocumuliform: Wave and haze clouds that are seen mostly in the middle layer. ; Cumuliform and cumulonimbiform: Convective clouds in the lowest layer that are capable of producing

and may be composed at least partly of water droplets. an intermediate deck of

ammonium hydrosulfide Ammonium hydrosulfide is the chemical compound with the formula . Composition It is the salt derived from the ammonium cation and the hydrosulfide anion. The salt exists as colourless, water-soluble, micaceous crystals. On Earth the compound ...

, and an inner deck of cumulus water clouds.

Uranus and Neptune

Cloud layers composed mainly of

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes ...

gas. ; Cirriform: High wispy formations resembling cirrus. ; Stratiform: Layers of haze-cloud that lack any distinct features. ; Cumuliform and cumulonimbiform: Lower-based convective clouds that can produce thunderstorms.

Notes and references

External links

Introduction to Clouds (National Weather Service)Ten Basic Cloud Types (National Weather Service)International Cloud Atlas online (Archived)Cloud Appreciation Society

UK Met Office cloud classification pageCloud Atlas (Atlas Chmur)
(in Polish)
NOAA
{{DEFAULTSORT:List Of Cloud Types Satellite interpretation Weather-related lists lv:Mākoņu veidu uzskaitījums pl:Chmura#Klasyfikacja chmur

Cloud identification and classification: Order of listed types

Cloud cross-classification throughout the homosphere

Mesospheric cloud identification and classification

Extreme-level stratiform, stratocumuliform, and cirriform

Stratospheric cloud identification and classification

Very high-level stratiform

Very high-level cirriform and stratocumuliform

Troposphere cloud identification and classification

High-level cirriform, stratocumuliform, and stratiform

Genus cirrus

=Species

=Varieties

=Supplementary features

Genus cirrocumulus

=High stratocumuliform species

=Varieties

=Supplementary features

Genus cirrostratus

=Species

=Varieties

=Supplementary features

Mid-level stratocumuliform and stratiform

Genus altocumulus

=Mid-level stratocumuliform species

=Varieties

=Supplementary features

Genus altostratus

=Species

=Varieties

=Supplementary features

Towering vertical cumulonimbiform and cumuliform (low to mid-level cloud base)

Genus cumulonimbus: Towering vertical

=Species

=Varieties

=Supplementary features

Genus cumulus: Towering vertical

=Species

=Varieties

=Supplementary features

Multi-level stratiform and moderate vertical cumuliform (low to mid-level cloud base)

Genus nimbostratus: Multi-level

=Species

=Varieties

=Supplementary features

Genus cumulus: Moderate vertical

=Species

=Varieties

=Supplementary features

Low-level stratocumuliform, cumuliform, and stratiform

Genus stratocumulus

=Species

=Varieties

=Supplementary features

Genus cumulus (little vertical extent)

=Species

=Varieties

= Supplementary features and accessory clouds

Genus stratus

=Species

=Varieties

=Supplementary features

Tropospheric cloud types with Latin etymologies where applicable

WMO genera

WMO species

WMO varieties

WMO supplementary features

Genitus mother clouds

Other genitus clouds

Mutatus mother clouds

Informal terms recently accepted for WMO classification with Latin nomenclature

WMO and informal terms related to free-convective cloud types and storms

Other planets

Venus

Mars

Jupiter and Saturn

Uranus and Neptune

See also

Notes and references

External links