A video being shared on social media shows an odd looking colorful cloud that looks a bit like a translucent disc hovering over a storm cloud.
It actually is a translucent disc hovering over a storm cloud. It's a type of cloud know as Pileus, or a cap cloud, which is formed above a cumulonumbus cloud (a storm cloud) by the strong updraft. Seeing a pileus cloud indicates that the storm cloud is growing rapidly.
The colors are a cloud phenomenon known as iridescence. This occurs in transparent clouds when the droplets in the clouds are all similar sizes (typically this occurs in very young clouds). The similar sized droplets scatter light of a particular color, and small variations in the size, combined with the angle from the sun, create irregular bands of color.
A google search shows many similar phenomena:
For more details and examples, see: