All high clouds are a type of cirrus, a common cloud that can be seen at any time of the year.
Height of base: 18,000 - 40,000 ft
Shape: Layered, tufty or patchy
Latin: cirrus - lock or tuft of hair
Cirrus are short, detached, hair-like clouds found at high altitudes. These delicate clouds are wispy with a silky sheen or look like tufts of hair. In the day time, they are whiter than any other cloud in the sky. While the sun is setting or rising, they may take on the colours of the sunset.
They are made of ice crystals which provides their white colour and form in a wide range of shapes and sizes. They often form in advance of a warm front where the air masses meet at high levels.
Last updated: 18 April 2016