(MONUMENT, Colo.) — You’ve got to be a little lucky to catch them as they don’t last very long once they’ve formed. Kelvin-Helmholtz (Kh) clouds, also known as fractus clouds, are named for Lord Kelvin and Hermann von Helmholtz, who studied the physics of the instability that leads to these clouds that often look like ocean waves.

Our Hanson Hot Spring Spas camera in Monument caught several rounds of Kh waves Tuesday morning, Aug. 13, as low-level moisture pushed up against the Palmer Divide behind Monday night’s thunderstorms.

In the below timelapse, you’ll see the clouds on the right-hand side of the video, and as you get toward the middle, the clouds appear in the center of the frame, including the best ones of the bunch. Even toward the end of the video a few more form on the left-hand side.

These clouds form into the wave shapes you see when the air above them is moving more quickly than the air in the clouds, pushing over the tops of the clouds and creating a rolling wave appearance. We often see them around here during morning temperature inversions when this velocity shear is present.

Below is a still frame of the crispest waves that formed early Tuesday.