Beautiful Banner Peak at the west end of Thousand Island Lake! Tyson Fisher captures some of the magic of the High Sierra.
Banner Peak was named in 1883 by USGS topographer Willard D. Johnson who observed a banner cloud streaming from the summit. A banner cloud is a stationary cloud that develops downwind of an mountain crest or isolated peak and takes the shape of a banner or a flag streaming from the mountain peak. (This type of cloud must not be confused with snow which is blown off a mountain summit and carried downwind.) A banner cloud tends to form downwind of the upper slopes of steep-sided mountains. This cloud is similar to the condensation observed off aircraft wings flying in humid conditions; it is created by the vortices and local uplifting in the air as the wind passes the mountain. The most famous such cloud forms routinely in the lee of the Matterhorn (see the second photo).
