Cirrus clouds are made up of ice crystals that form when supercooled water droplets freeze. These wispy and thin clouds are usually at elevations higher than 20,000 feet and are created from other clouds that go through a process called glaciation. Cirrus clouds appear in a number of shapes and sizes and are commonly seen in areas with fair weather.
Cirrus clouds can appear as finger-like streaks or can be more uniform in texture when close to approaching warm fronts. Streaks within cirrus clouds can appear in many different sizes and shapes and can also stretch vertically and horizontally. The primary factors involved in the shaping of cirrus clouds are elevation, wind changes and how rapidly the ice crystals within the clouds fall.