What are cirrus clouds made of?
Cirrus clouds are high and thin and made entirely of ice crystals. Forming above 20,000 feet in the atmosphere, they often look like wisps of white hair. Cirrus clouds, which are a sign of warm moist air rising up over cold air, are sometimes an early signal that thickening clouds could bring light rain or snow within one or two days. Cirrus: It’s Latin for “curl.” Cirrus clouds look like curls of white hair.
