Such clouds, according to scientists, appear when cold layers of air near the earth's surface collide with warmer and faster moving currents above them. A striking example of this phenomenon is sea waves, since the wind above the water surface moves faster than waves, then crests are formed on them.
This phenomenon is not very frequent, therefore, there are not so many photographs that have recorded this phenomenon.
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"In the world" these clouds are called Van Gogh's clouds - in his painting "Starry Night" there are similar whimsical cloud curls. Perhaps the artist was inspired by the beautiful and rare clouds.