Kelvin-Helmholtz wave clouds. Time-lapse footage of strong wind shears curling high-altitude clouds into a distinctive and ephemeral Kelvin-Helmholtz wave pattern. This distinct corkscrew pattern is formed by layers of air moving across each other in opposite directions, creating a series of circular air movements in between them. This type of cloud generally forms at high altitude and dissipates rapidly. The formation seen here is associated with a jet stream in the lee of the Rocky Mountains. Filmed on a winter's afternoon in Colorado, USA.