"Cool Met Stuff": Why are clouds white or grey at times?

1 August 2025

Blue skies and white clouds can be observed on sunny days, and clouds appear grey and dark on rainy days. Have you ever wondered how the colours of clouds are formed? The latest episode of "Cool Met Stuff" will explain the structure of clouds in detail and explores the optical physics behind the changes in cloud colour.

The video is now available on the "MyObservatory" mobile application and the Observatory's website for your viewing (programme is broadcasted in Cantonese).

Welcome to view "Cool Met Stuff" from this link (broadcast in Cantonese).
Broadcast schedule of various TV channels can be found here.