Why are cirrpcumulus clouds sometimes called mackerel?

Cirrrocumulus clouds are sometimes referred to as "mackerel skies" because their appearance resembles the scales of a mackerel fish. This name is derived from the cloud's characteristic pattern of small, white patches or ripples that often form in rows at high altitudes. The term highlights the aesthetic similarity between the cloud formations and the fish's scaled skin, which can serve as a visual cue for changing weather conditions.