If the weather situation is calm, every morning when the sun rises, a wave-shaped cloud, 1.6 to 3.2 km. high and 600 to 1,000 km., i.e., that it fills the horizon, moving at a speed of 40 km. per hour.
In the early hours of the morning, a mass of warm, moist air, from the sea, slips over the cooler air that is in the upper layers. In late 2006, scientists from several countries traveled to study the phenomenon, which occurs in many places in the world. It has been observed on the Catalan coast of Spain.
Since 1989, every spring, when the phenomenon occurs, hang gliders and paragliders cloud surf waves like waves in an ocean. You have to be careful because the waves produce strong turbulence and can be dangerous. They fly in zigzag patterns and can travel up to 480 kilometers