Why don't rainbows appear on clouds?

It DOES appear on the clouds, few and far between. But they don't call it as rainbows. The meteorological terminology for that phenomenon is Iridescence, and the clouds are Iridescent clouds. read more

It DOES appear on the clouds, few and far between. But they don’t call it as rainbows. The meteorological terminology for that phenomenon is Iridescence, and the clouds are Iridescent clouds. It is quite an unusual phenomenon and is most often observed in high étages like Cirrus, Cirrocumulus and Altocumulus clouds. read more

Important for a rainbow to appear is not when the rain appears but where: you see a rainbow when unobstructed sun is shining from behind you, raindrops in front of you and the angle between you, the raindrops and the sun is 42 degrees. read more