A Pileus cloud, also referred to as a cap cloud and a scarf cloud, was visible in Haikou on August 21. A pileus is created when the quickly rising air in the cumulonimbus (also known as a cumulus cloud) updraft pushes against the cooler air above it. The moisture condenses as a result right along the top of the updraft, resulting in the Pileus' development.
When the sun is shining at just the perfect angle, light is reflected between the cloud's ice crystals and droplets, giving the Pileus its rainbow-like colors. But these clouds typically only last a few hours. This is because they are "eaten up" by the cloud that is above them; Pileus is absorbed by the lower cloud by convection.
Pileus clouds are a favourite among cloud-spotters. They aren't very common, but if you know where to look, you can spot them on days when you could anticipate cumulus clouds developing into thunderstorms.
If you're fortunate enough to see one, pileus cloud formations can be incredibly beautiful even though they rarely last for more than a few minutes. They should not be confused with the lenticular cloud, a near relative. Lenticular clouds stand alone while pileus clouds are an accessory to cumuliform clouds.
Lenticular clouds, so named because they resemble lentils, are easily distinguished from other cloud species by their distinctive UFO shape and smooth edges.
Meanwhile, a Twitter user shared a photograph from Jodhpur, Rajasthan and wondered if we could call it rainbow clouds. The photo does show something that somewhat looks usual in shape. However, it is colourful and looks like a rainbow.
