Based ~ above his observations, Luke Howard said there were modifications (or combinations) of the core 4 clouds between categories. The noticed that clouds regularly have features of two or much more categories; cirrus + stratus, cumulus + stratus, etc. His study served as the starting point because that the ten basic types that clouds we observe.

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From the people Meteorological Organization's (WMO) International Cloud Atlas, the official worldwide standard because that clouds, the following are definitions of the ten simple cloud types. Split by their height the ten species of clouds are...

High-Level Clouds

Cirrus (Ci), Cirrocumulus (Cc), and also Cirrostratus (Cs) space high level clouds. They are commonly thin and also white in appearance, but can appear in a magnificent range of colors as soon as the sun is low on the horizon.

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

Cirrus clouds are constantly composed of ice crystals, and their transparent character counts 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. When they are exceptionally special they may veil its light and also obliterate that is contour.

Before sunrise and also after sunset, cirrus is frequently colored shining yellow or red. This clouds are lit increase long before other clouds and fade out lot later; part time ~ sunset they become gray.

At all hours of the day Cirrus near the horizon is frequently of a yellowish color; this is due to distance and also to the great thickness of waiting traversed by the beam of light.

Thin, white patch, sheet, or layered the clouds there is no shading. They room composed of very little elements in the kind of much more or much less regularly arranged seed or ripples.

Most of these facets have an noticeable width of less than one degree (approximately broad of the little finger - in ~ arm's length).

In general, Cirrocumulus to represent a degraded state that cirrus and also cirrostratus, both of which may change into it and also is an unusual cloud. There will be a connection with cirrus or cirrostratus and will display some characteristics of ice crystal clouds.


Transparent, whitish veil clouds through a fibrous (hair-like) or smooth appearance. A paper of cirrostratus which is really extensive, virtually always ends by covering the entirety sky.

During the day, once the sun is sufficiently high above the horizon, the sheet is never ever thick sufficient to protect against shadows the objects ~ above the ground.

A milky veil that fog (or thin Stratus) is identified from a veil the Cirrostratus the a comparable appearance by the halo phenomena which the sun or the moon almost always produces in a class of Cirrostratus.

Mid-Level Clouds

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

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

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

Most of these on regular basis arranged little elements have actually an apparent width that one come five degrees (larger 보다 the tiny finger and also smaller than 3 fingers - at arm's length).

When the edge or a slim semitransparent job of altocumulus passes in prior of the sun or moon, a corona appears. This colored ring has red top top the outside and also blue inside and also occurs in ~ a few degrees of the sunlight or moon.

The most usual mid cloud, an ext than one layer of Altocumulus often shows up at different levels in ~ the same time. Countless times Altocumulus will appear with other cloud types.

Gray or bluish cloud sheets or layers of striated or fibrous clouds that entirely or partially covers the sky. They space thin enough to consistently reveal the sunlight as if seen v ground glass.

Altostratus clouds carry out not create a aur phenomenon nor room the shadows the objects top top the floor visible.

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

Resulting native thickening Altostratus, This is a dark gray cloud layer diffused by fallout’s rain or snow. The is thick enough throughout to blot out the sun. Also, low, ragged clouds typically occur in ~ this cloud which periodically merges through its base.

The cloud base lowers as precipitation continues. Because of the lowering base it is often erroneously called a low-level cloud. Both Altostratus and also Nimbostratus can prolong into the high level of clouds.

Low-Level Clouds

Cumulus (Cu), Stratocumulus (Sc), Stratus (St), and also Cumulonimbus (Cb) room low clouds written of water droplets. Cumulonimbus, v its solid vertical updraft, extend well into the the high level the clouds.

Detached, generally thick clouds and also with sharp outlines that construct vertically in the type of rising mounds, domes or towers through bulging top parts often resembling a cauliflower.

The sunlit parts of these clouds are mostly brilliant white while their bases are reasonably dark and horizontal.

Over floor cumulus establishes on days of clear skies, and is early out diurnal convection; it shows up in the morning, grows, and also then more or less dissolves again towards evening.

The thunderstorm cloud, this is a heavy and also dense cloud in the form of a hill or large tower. The upper part is generally smoothed, fibrous or striated and nearly always planarization in the form of one anvil or vast plume.

Under the basic of this cloud which is often an extremely dark, over there are often low ragged clouds that might or may not merge v the base. They create precipitation, which sometimes is in the kind of virga.

Cumulonimbus clouds likewise produce hail and also tornadoes.

Gray or whitish patch, sheet, or layered clouds which almost always have actually dark tessellations (honeycomb appearance), rounded masses or rolls. Other than for virga they are non-fibrous and also may or may not be merged.

They likewise have regularly arranged little elements v an obvious width of an ext than five degrees (three fingers - at arm's length).

A usually gray cloud layer through a uniform base which may, if special enough, develop drizzle, ice cream prisms, or snow grains. Once the sun is visible with this cloud, its overview is plainly discernible.

Often once a great of Stratus breaks up and also dissipates blue skies is seen.

Sometimes showing up as ragged sheets Stratus clouds carry out not develop a halo phenomenon except, occasionally at an extremely low temperatures.

Fast Facts

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

Clouds out my home window is easily accessible for free. In ~ the end of the book is a connect to a Power allude template to do your very own "Clouds out my Window" book.

Fast Facts

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

See more: Why Did The Cottage Industry Disappear? ? Why Did The Cottage Industry Disappear

Clouds out my window is obtainable for free. In ~ the finish of the book is a connect to a Power allude template to do your very own "Clouds the end my Window" book.

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