How Rare Is a Rainbow Cloud?

These clouds that look like rainbows aren't very common, but chances are you've seen one or two in your life.

What happens if you see a rainbow cloud?

Iridescent clouds, known as "fire rainbows" or "rainbow clouds," occur when sunlight diffracts off water droplets in the atmosphere. And the recipe for these heavenly sights is actually pretty simple. Like common cloud-to-ground rainbows, iridescent clouds usually accompany thunderstorms.

Is a fire rainbow rare?

As mentioned above, fire rainbows are rare. The source of light—the Sun (or Moon)—needs to be at least 58o above the horizon, meaning that fire rainbow is almost impossible to see in places north of 55oN or south of 55oS.