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Cloud Types

Most clouds are associated with weather. These clouds can be divided into groups mainly based on the height of the cloud's base above the Earth's surface. The following table provides information about cloud groups and any cloud classes associated with them. In addition, some clouds don't fall into the categories by height. These additional cloud groups are listed below the high, middle, and low cloud groups.

Cloud Group and Height * Cloud Types
High Clouds
5,000-13,000m
(Noctilucent clouds are the highest clouds in the sky, however they are not associated with weather like the rest of the clouds in this table.)
Middle Clouds
2,000-7,000m
Low Clouds
Surface-2,000m
Unusual Clouds
(View cloud heights on each cloud's individual page)
Contrails
5,000-13,000m

* The cloud heights provided in this table are for the mid-latitudes. Cloud heights are different at the tropics and in the polar regions. In addition, a few other cloud types are found in higher layers of the atmosphere. Polar stratospheric clouds are located in a layer of the atmosphere called the stratosphere. Polar mesoshperic, or noctilucent, clouds are located in the atmospheric layer called the mesosphere.

Clouds

How Clouds Form

CMMAP - Studying Clouds and Climate

Clouds in Art

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Last modified May 21, 2009 by Becca Hatheway.

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High Clouds

The high cloud group consists of Cirrus, Cirrostratus, and Cirrocumulus clouds. High clouds are made of ice crystals due to the cold air in the upper sky. The base of a high cloud above the surface can...more

Noctilucent Clouds

Noctilucent clouds (NLC’s) or polar mesospheric clouds (PMC’s) are found very high in the Earth's atmosphere. They are called Polar Mesospheric Clouds when they are viewed from space, and are referred...more

Cirrus

Cirrus clouds are the most common of the High Cloud (5000-13000m) group. They are composed entirely of ice and consist of long, thin, wispy streamers. They are commonly known as "mare's tails" because...more

Cirrocumulus

Cirrocumulus clouds belong to the High Cloud group (5000-13000m). They are small rounded puffs that usually appear in long rows. Cirrocumulus are usually white, but sometimes appear gray. Cirrocumulus...more

Cirrostratus

Cirrostratus clouds belong to the High Cloud (5000-13000m) group. They are sheetlike thin clouds that usually cover the entire sky. The sun or moon can shine through cirrostratus clouds . Sometimes, the...more

Middle Clouds

The middle cloud group consists of Altostratus and Altocumulus clouds. Middle clouds are made of ice crystals and water droplets. The base of a middle cloud above the surface can be anywhere from 200...more

Altocumulus

Altocumulus clouds are part of the Middle Cloud group (2000-7000m up). They are grayish-white with one part of the cloud darker than the other. Altocumulus clouds usually form in groups and are about...more

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