Cirrostratus / ˌ s ɪr oʊ ˈ s t r ɑː t ə s / is a high-level, very thin, generally uniform stratiform genus-type of cloud.It is made out of ice-crystals, which are pieces of frozen water.It is difficult to detect and it can make halos.These are made when the cloud takes the form of thin cirrostratus nebulosus. However, as they are relatively transparent, the Sun or the Moon can easily be seen through them. Cirrostratus Clouds sheet-like and nearly transparent Cirrostratus are sheet-like, high-level clouds composed of ice crystals. Cirrostratus nebulosus is a species of high-level cirrostratus cloud.The name cirrostratus nebulosus is derived from Latin, the adjective nebulosus meaning "full of vapor, foggy, cloudy, dark". How do cirrostratus clouds form? Cirrostratus are high-level clouds, appearing as a thin hazy, uniform and featureless whitish and smooth veil.Cirrostratus are darker than cirrus and are always thin enough for the high Sun to cast shadows. It is normal to expect a deterioration of the weather conditions within 12 to 24 hours after cirrostratus clouds have been observed. Cirrostratus clouds are formed during periods of peaceful weather, but their formation normally indicates that a period of fine weather is coming to an end. As a result of slowly rising air, cirrostratus cloud can form. The Sun often cannot cast shadows when shining through altostratus clouds. Altostratus layers are often composed of both water and ice and usually form when a layer of cirrostratus descends from a higher level. Stratiform clouds that both extend through a large fraction of the troposphere and precipitate are called nimbostratus. Cirrostratus clouds are sheetlike, thin, high-level clouds that occur when cirrus clouds spread out into thin, milky layers. Like all cirrus clouds, they are made of ice crystals.

These layers can sometimes contribute to the formation of optical effects such as coronas and iridescence. The clouds can cover the whole sky. Usually generated at the forefront of frontal weather systems the movements of cirrostratus can be used to predict what the weather will do in the next 24 hours. Cirrostratus is a member of the ten fundamental cloud types (or cloud genera). Though cirrostratus can cover the entire sky and be up to several thousand feet thick, they are relatively transparent, as the sun or the moon can easily be seen through them. They usually appear 12-24 hours before rain or snow . The cirrus cloud type refers to thin, often wispy, cirrostratus clouds. Other articles where Cirrostratus is discussed: atmosphere: Cloud formation within the troposphere: …the upper troposphere, the terms cirrostratus and cirrus are used. Cirrostratus (Cs) - the name is a composite of the Latin cirrus = wisp or curl and stratus = layer.