They look like clouds, but are actually made of ice. Cirrus clouds, derived from the Latin for ringlet or curly lock of hair, often announce a change in the weather – for example, when a warm front is approaching.
In this case, warm air glides slowly on the heavier cold air. These fascinating feathery clouds are then created at altitudes of 8,000 to 10,000 metres. A change in the weather is certain if the cirrus cloud becomes a cirrostratus forming a continuous cloud layer. It could be another 24 hours before the bad weather arrives, during which other types of cloud can be seen, at last the dark nimbostratus from which rain falls. Meteorology names a total of four different cloud families that occur at different altitudes. These in turn are subdivided into ten cloud categories. Each one represents a specific weather phenomenon. However, interpreting these phenomena is difficult and requires a lot of experience.
