Another Rotating Cloud: An Additional Comment On “Rotating Clouds at Norman, Oklahoma”

Abstract

On 1 July 1969 I photographed a spectacular cumulonimbus buildup some 10 miles east of Boulder, Colo. (cover photo). Comments on this cloud with colleagues at NCAR put me in contact with NCAR's chief photographer, James Digby. He had returned to Boulder that evening from an assignment. Standing on the roof of his garage, he had shot the remaining film in his movie camera in stop-motion mode. Unfortunately this amounted in real time only to 1?2 minutes in length. However, the counterclockwise rotation of the cloud mass was most impressive. To the best of my knowledge there was no tornado associated with the could. (A recent telephone conversation with Digbv, now with Eastman Kodak, Windsor, Colo., advises this film is on file at NCAR under the Hail Project materials.)