Based on his observations, Luke Howard said there were modifications (or combinations) the the core 4 clouds between categories. The noticed that clouds frequently have functions of 2 or more categories; cirrus + stratus, cumulus + stratus, etc. His research study served as the beginning point for the ten simple types the clouds us observe.

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From the people Meteorological Organization's (WMO) International Cloud Atlas, the official an international standard because that clouds, the complying with are meanings of the ten simple cloud types. Separated by their height the ten species of clouds are...

High-Level Clouds

Cirrus (Ci), Cirrocumulus (Cc), and also Cirrostratus (Cs) are high level clouds. They are commonly thin and also white in appearance, yet can show up in a magnificent array of colors as soon as the sun is short on the horizon.

Detached clouds in the kind of white, delicate filaments, largely white patches or narrow bands. They may have actually a fibrous (hair-like) and/or silky sheen appearance.

Cirrus clouds are always composed of ice crystals, and also their transparent character relies upon the degree of separation the the crystals. Together a rule, when these clouds cross the sun's disk lock hardly to decrease its brightness. Once they space exceptionally thick they might veil that light and also obliterate the contour.

Before sunrise and also after sunset, cirrus is frequently colored shining yellow or red. This clouds space lit up long prior to other clouds and fade out lot later; part time after ~ sunset they end up being gray.

At all hours of the job Cirrus close to the horizon is often of a yellowish color; this is as result of distance and to the great thickness of air traversed by the beam of light.

Thin, white patch, sheet, or layered that clouds there is no shading. They are composed of very small elements in the form of more or much less regularly arranged grains or ripples.

Most that these aspects have an apparent width of much less than one level (approximately width of the little finger - at arm's length).

In general, Cirrocumulus to represent a degraded state of cirrus and cirrostratus, both of i m sorry may adjust into it and is an unusual cloud. There will be a link with cirrus or cirrostratus and also will present some qualities of ice crystal clouds.


Transparent, whitish veil clouds v a fibrous (hair-like) or smooth appearance. A paper of cirrostratus which is an extremely extensive, almost always ends by covering the totality sky.

During the day, once the sun is sufficiently high above the horizon, the paper is never ever thick sufficient to stop shadows of objects ~ above the ground.

A milky veil of fog (or slim Stratus) is differentiated from a veil the Cirrostratus that a comparable appearance through the gloriole phenomena i beg your pardon the sunlight or the moon practically always produce in a class of Cirrostratus.

Mid-Level Clouds

Altocumulus (Ac), Altostratus (As), and also Nimbostratus (Ns) are mid-level clouds They are composed primarily of water droplets. However, lock can likewise be created of ice crystals when temperatures room low enough.

In Latin, alto way 'high' however Altostratus and Altocumulus clouds are classified as mid-level clouds. 'Alto' is offered to differentiate these "high-level" clouds and their low-level liquid-based counterpart clouds; Stratus and Cumulus.

White and/or gray patch, paper or layered clouds, usually composed the laminae (plates), rounded masses or rolls. They might be partially fibrous or diffuse and also may or may not be merged.

Most that these on regular basis arranged small elements have an evident width the one to five levels (larger than the little finger and also smaller than 3 fingers - at arm's length).

When the sheet or a slim semitransparent spot of altocumulus passes in prior of the sunlight or moon, a corona appears. This fancy ring has red on the outside and also blue inside and occurs within a couple of degrees that the sun or moon.

The most common mid cloud, an ext than one class of Altocumulus often shows up at various levels at the same time. Many times Altocumulus will show up with various other cloud types.

Gray or bluish cloud sheets or class of striated or fibrous clouds that completely or partly covers the sky. They space thin enough to consistently reveal the sun as if seen through ground glass.

Altostratus clouds do not produce a gloriole phenomenon nor room the shadows that objects on the soil visible.

Sometime virga is viewed hanging from Altostratus, and also at times may even reach the floor causing very light precipitation.

Resulting from thickening Altostratus, This is a dark gray cloud great diffused by fall rain or snow. The is thick enough throughout come blot the end the sun. Also, low, ragged clouds frequently occur in ~ this cloud which periodically merges through its base.

The cloud basic lowers together precipitation continues. Due to the fact that of the lowering basic it is often erroneously dubbed a low-level cloud. Both Altostratus and Nimbostratus can expand into the high level of clouds.

Low-Level Clouds

Cumulus (Cu), Stratocumulus (Sc), Stratus (St), and Cumulonimbus (Cb) are low clouds written of water droplets. Cumulonimbus, through its strong vertical updraft, extend well right into the the high level of clouds.

Detached, generally thick clouds and with sharp outlines that construct vertically in the type of increasing mounds, domes or towers v bulging upper parts often resembling a cauliflower.

The sunlit components of these clouds are greatly brilliant white while their bases are relatively dark and also horizontal.

Over soil cumulus develops on job of clear skies, and is early diurnal convection; it appears in the morning, grows, and also then more or less dissolves again toward evening.

The thunderstorm cloud, this is a heavy and dense cloud in the form of a mountain or huge tower. The upper section is usually smoothed, fibrous or striated and nearly always planarization in the shape of one anvil or large plume.

Under the base of this cloud i beg your pardon is often really dark, there are often low ragged clouds that may or may not merge with the base. They create precipitation, which sometimes is in the form of virga.

Cumulonimbus clouds also produce hail and tornadoes.

Gray or whitish patch, sheet, or layered clouds which virtually always have actually dark tessellations (honeycomb appearance), rounded masses or rolls. Other than for virga they room non-fibrous and may or might not it is in merged.

They likewise have on regular basis arranged small elements through an noticeable width of much more than five degrees (three fingers - in ~ arm's length).

A generally gray cloud layer through a uniform base which may, if thick enough, produce drizzle, ice cream prisms, or eye grains. Once the sun is visible with this cloud, its outline is clearly discernible.

Often once a layer of Stratus breaks up and also dissipates blue sky is seen.

Sometimes appearing as ragged sheets Stratus clouds do not produce a aur phenomenon except, occasionally at really low temperatures.

Fast Facts

John "Dr. Lightning" Jensenius, retirement NWS Meteorologist, produced a PDF "Cloud Book" dubbed "Clouds out my Window".

Clouds the end my home window is accessible for free. At the end of the publication is a connect to a Power point template to make your very own "Clouds out my Window" book.

Fast Facts

John "Dr. Lightning" Jensenius, retired NWS Meteorologist, produced a PDF "Cloud Book" referred to as "Clouds the end my Window".

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Clouds out my home window is easily accessible for free. At the end of the book is a link to a Power allude template to make your very own "Clouds the end my Window" book.

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