BILLOWLY HAIR-LIKE Whitish high cloud composed of small billow-like cloud elements. Some turbulence may be experienced when flying through Cc. Not often observed.
VEIL-LIKE LAYERWhitish viel-like high cloud made of crystals. It is usually translucent and has a smooth appearance. The sun, when viewed through Cs, is often seen surrounded by a rainbow-like ring called a 'solar halo'. This cloud invades the sky well ahead of a frontal system and may thicken to Altostratus as the front approaches.
HAIR-LIKEWhite, fibrous-looking cloud made of ice crystals. This cloud is often the first sign of a front approaching. Cirrus streaks are sometimes known as 'mares' tails'.