english: This looks like a series of breaking waves, and it's caused by shearing winds -- the wind above the cloud layer and below the cloud layer differ significantly, and in the middle, in between, you get this undulating of the air, and if the difference in those speeds is just right, the tops of the undulations curl over in these beautiful breaking wave-like vortices.
non_english: Izgleda kao serija talasa koji se lome, prouzrokovan promenljivim vetrovima - iznad i ispod sloja oblaka značajno se razlikuju a u sredini, između, imamo talasanje vazduha i ako je razlika u brzinama prava, vrhovi talasa uvijaju se u ove isprekidane talasaste vrtloge.