Clouds: Thunderstorms (894, 3317C, 3835B), 1969-1976

(894) Thunderstorm clouds, NCAR east, by radar from Greeley, frames 1-23, afternoon, August 15, 1969; (3317C) Aerial view of a thunderstorm showing gravity wave overflow, January 16, 1976, photographed by Alf Modahl; (3835B) Clouds, thunderstorm north of Lafayette, Colorado in 1965, NCAR Photographics Lab date: December 28, 1976.