ORLANDO, FL.A unusual and exquisite optical phenomena was glimpsed by a number of localities that experienced storms on Tuesday night.
This is, in my opinion, among the most exquisitely unique things I have ever seen! Tonight’s rainbow-tipped cloud, as viewed from my backyard following a downpour.
Lisa Miller
These are referred to as iridescent pileus clouds.
In actuality, two things are happening here.
Cloud formation with a rainbow effect, 6:55 p.m. today, 2025-07-29. Looking west at Curryford Road at Dean Road
The first was the pileus cloud formation. These clouds develop over a bigger, expanding cloud, like a cumulonimbus cloud from a thunderstorm.
They develop as moist air is forced above the expanding cloud by powerful updrafts, condensing into a thin cap-like structure.
These clouds are usually transient because the pileus cloud is consumed by the main rising cloud.
Cloud iridescence is the second component, the rainbow component.
It happens when ice crystals or microscopic water droplets in a thin, smooth cloud refract sunlight. In this instance, the pileus cloud over the forming thunderstorm was the thin, smooth cloud.
A rainbow-like display of hues is produced via diffraction, which occurs when light bends around the particles.
These typically arise on hot, muggy days when thunderstorms are growing quickly. For light to travel through the atmosphere and reach the clouds, the sun must also be at a lower angle.
On Tuesday, temperatures in central Florida reached all-time highs, and storms began to blow about dusk.
The circumstances were ideal for simultaneously capturing two atmospheric occurrences.
The weather team at News 6 makes sure you’re always aware of the conditions during the day.
