Why Do Some Clouds Look Flat Underneath? #Video

Have you ever noticed that many clouds seem to have perfectly flat bottoms? It may look like someone sliced them across the sky, but there’s actually a fascinating scientific reason behind it.

In this episode of History of Simple Things, we explore how rising warm air, cooling temperatures, and an invisible atmospheric boundary determine where clouds begin to form. That smooth underside is the point where water vapor finally condenses into tiny droplets, making the cloud visible.