Cirrus Clouds

Cirrus clouds forming in tufts

Cirrus clouds are clouds that are very thin and that form at high altitudes. When water vapor freezes at altitudes higher than 20,000ft, Cirrus clouds are formed.

Cirrus clouds over a field

Cirrus clouds are normally characterized by their thin wispy strands and tufts. Cirrus clouds are associated with fair to pleasant weather.

http://eo.ucar.edu/webweather/cirrus.html

http://www.absoluteastronomy.com/topics/cirrus_cloud

http://en.wikipedia.org/wiki/File:CirrusField-color.jpg

http://www.windows.ucar.edu/tour/link=/earth/climate