Clouds Formation

- Genus Cirrostratus (Cs): A thin non-convective ice crystal veil that typically gives rise to halos caused by refraction of the sun's rays. The sun and moon are visible in clear outline. Cirrostratus typically thickens into altostratus ahead of a warm front or low pressure area.
+ Species Cirrostratus fibratus (Cs fib): Fibrous cirrostratus less detached than cirrus.
+ Species Cirrostratus nebulosus (Cs neb): A featureless veil of cirrostratus.