Cirrostratus clouds

The thin, layered Cirrostratus cloud is composed of ice crystals and forms a veil that covers all or part of the sky.

Symbol: Cirrostratus symbol

Height of base: 18,000 - 40,000 ft

Shape: Layered

Latin: cirrus - lock or tuft of hair; stratus - flattened or spread out

Precipitation: None

Cirrostratus cloud (Photo: Matthew Clark) Cirrostratus cloud (Photo: Matthew Clark)

Cirrostratus are transparent high clouds covering large areas of the sky. They sometimes produce white or coloured rings, spots or arcs of light around the sun or moon that are known as halo phenomena. Sometimes they are so thin that the halo is the only indication that a cirrostratus cloud is in the sky.

Cirrostratus can span thousands of miles, and may be smooth or fibrous and are often fringed with cirrus clouds.

Shadows will normally still be cast by the sun when shining through cirrostratus clouds, which can help distinguish them from similar nimbostratus clouds.

Similar clouds

  • Cirrus
    All high clouds are a type of cirrus, a common cloud that can be seen at any time of the year.

  • Cirrocumulus
    Cirrocumulus are a relatively rare cloud forming ripples which may resemble honeycomb.

Last updated: 6 August 2014