When we look at clouds, we think of them as drifting slowly across the sky. But sometimes that's not at all how they move. Santa Barbara lies between the Pacific ocean and the Santa Ynez mountains. Often, the clouds I see from my house are not drifting at all, though you would not normally notice. Instead, they condense out of the sea air rising up to the mountains. The clouds stay pretty much in the same place, but they condense and evaporate in place rather than floating by in a stream. Sometimes there is a single cloud over the mountains, caused by a local low pressure area over a particular spot in the terrain. This lone cloud will grow and shrink, but does not move.

This movie was made by capturing an image every six seconds, then playing them back at 25 frames per second. This compresses time by a factor of 150 and reveals the motion of the clouds which, otherwise, is practically invisible.

Bryan Mumford
Santa Barbara, California