photo #5041058

This line of Stratocumulus fluctus spotted by Steve Shaw (Cloud Appreciation Society member 2,468) is a short-lived cloud shaped by wind shear. This is when there is a marked difference in wind speed or direction above and below at the cloud. Faster winds above pick up the tops of undulations in the upper surface of the cloud and curl them over to resemble ocean breakers. Steve spotted them from the back garden of his home near Bude, Cornwall, England, a popular surfing spot. Fluctus, which are also known as Kelvin-Helmholtz clouds, tend to break up only for a few minutes after they’ve formed, which is exactly what Steve’s did as the light faded in this summer evening sky.