Different Types Of Clouds
The different types of clouds form when water evaporates off of oceans, seas, rivers, lakes and ponds, and then condenses in the atmosphere. The various names of the different types of clouds are determined by how they form and what they look like to someone on the ground, using Latin words, both on their own and in combination, for appropriate descriptive adjectives. For example stratus is Latin for “layer” and nimbus is Latin for “rain”. Within each of these major cloud types there are various subtypes; Nimbostratus, for an example, and Cumulonimbus for another.
The different types of clouds fall into three categories that refer to the altitude levels at which they can be found. Cloud classification can be summed up in to three height levels for clouds and five description terms that rely on Latin words. The classifications looks like this:
Height Level | Altitude |
---|---|
High-level clouds | 20,000 feet and above |
Mid-level clouds | 6,500 to 20,000 feet |
Low-level clouds | Below 6,500 feet |
Descriptive Names | Latin Root:Translation |
---|---|
Cumulus | “Heap” |
Stratus | “Layer” |
Cirrus | “Curl of Hair” |
Nimbus | “Rain” |
Alto | “Mid” or “Middle” |
This cloud types chart is helpful for visualizing all of these different types of clouds.
The Highest Clouds
High-level clouds are primarily made of ice because they are formed at such high, and thus very cold, elevations. These clouds are often very thin and look starkly white during the day. When the sun is rising or setting, however, they will refract light in the atmosphere and can be adorned in a multitude of blues, purples, pinks, and reds. Cloud types in this range include the cirrostratus, cirrus, and cirrocumulus. These clouds tend to stretch over long areas when they form.
Cirrus clouds are wispy and often look feather-like. Meteorologists use these clouds as indicators of warm fronts moving through an area.
Cirrostratus clouds look like a thin, ribbed blanket or veil covering the sky. These clouds are known for creating a ring around the Sun or Moon when they lie in front of it. Their ice crystals refract light very well.
Cirrocumulus clouds usually form in layers with a lumpy or bumpy look. They often look like pieces of cotton tossed high in the sky but sometimes can form as large bumpy sheets. Cirrocumulus often show areas of the sky where clouds will ascend or descend.
Middle-elevation Clouds
The mid-level group of clouds is often made of a mixture of ice crystals and water droplets, though they usually have more droplets in the mix. In winter months, these clouds often do not contain snow except at lower elevations.
Clouds in this range include the altostratus and altocumulus clouds.
Altostratus clouds usually appear flat and uniform in shape, with the viewer being able to see sky above them clearly. These clouds usually enter areas when a warm front approaches and can thicken with water and fall into lower elevations to become rain and snow clouds.
Altocumulus clouds look like a low-sitting blanket with clumpy parts and show that two different air zones may be colliding.
Low-flying Clouds
Low-level clouds are your water-based clouds and often your rain clouds. When the weather gets cold, these are also the clouds that bring icy rain, sleet, and snow to your front door.
The nimbostratus and some stratocumulus clouds are the most common cloud types in this region.
Stratocumulus clouds are clumpy layered clouds that seem to go as high up as they do spread across. They are very common and usually show up in the sky before or after a front moves in.
Nimbostratus clouds are those that seem to blanket the entire sky at points and are often the clouds that create steady, heavy rain and snow. They are very long and can be short on sunny days.
Clouds are created by the accumulation of water vapor and ice in the atmosphere. Different names are given to clouds depending on what the clouds are made of, where they are located, and how they look.
The appearance-based naming aspect is relative to their observation by someone on the ground, not anything in the air.
Rarer Clouds and “Clouds”
Beyond these common clouds, there are also many other types of clouds that come in unique situations. Some of the more-common “special case” clouds include:
Wall Clouds:
These clouds look like fluffy walls and are typically a rain-free thunderstorm, which is often very strong. While there are many sizes and shapes, wall clouds that have strong updrafts can begin to rotation and may form tornadoes.
Shelf Clouds:
This is a thick, low and horizontal cloud that may have the general shape of a long wedge. These are usually found at the front of thunderstorms or rain-free storms that have very strong winds. These do not typically turn in to tornadoes.
Fractus Clouds:
Large, fluffy, and low are the three main characteristics of these clouds. They are rarely connected to thunderstorms or other weather patterns, despite their notoriously ominous dark hues.
Mammatus Clouds:
These clouds are often on the underside of a severe thunderstorm but they themselves do not create harsh storms. They are droopy and look like sheets of fluffy cotton. They are often a mix of whites and bronze colors.
Fog:
Fog is essentially a cloud that forms on the ground. There are many causes of fog, but it generally forms when moisture and water vapor accumulate near the ground very quickly, causing the cloud to become too heavy to rise.
Hole-punch Clouds:
These clouds look like a small mammatus but have large holes in them. They’re often created as the cloud’s temperature drops below freezing but the water itself isn’t frozen yet. As the water freezes, those portions of the cloud condense and drop, and holes form. In some cases, airplanes pass through near-freezing clouds and make the holes.
Mushroom Clouds:
The term “mushroom cloud” is somewhat of a misnomer because, strictly speaking, it doesn’t refer to a cloud in the meteorological sense. Meteorological clouds are formed by the condensation of water vapor in the atmosphere, and they are typically composed of tiny water droplets or ice crystals. A mushroom cloud, on the other hand, is a mushroom-shaped cloud of smoke, debris, and condensed water vapor that forms following a large explosion. The cloud’s mushroom appearance is a result of the physics involved in the explosion and subsequent atmospheric interactions.
Contrails:
Though, like mushroom clouds, not technically clouds in the meteorological sense, contrails form when the exhaust from a jet aircraft condenses at high altitudes. Contrails usually mean the high-level air is moist and moving.
Obscure Clouds
Below is a list of more obscure – but often the most interesting – different types of clouds.
Noctilucent Clouds
Asperitas or Asperatus Clouds
Undulatus Asperatus or Undlulatus Asperitas Clouds
Scud Clouds
Arcus Clouds
Polar Startospheric Clouds
Pileus Clouds
Nacreous Clouds