Why do clouds form?

How clouds form

Clouds form because warm air contains water vapor. When the Sun heats water on the ground, in rivers, lakes, and oceans, the water evaporates and rises into the air as invisible vapor.

As warm air rises, it becomes cooler. Cool air cannot hold as much water vapor as warm air, so the vapor condenses into tiny drops of water or ice crystals.

These tiny drops group together and form clouds. When the air continues to cool, more and more droplets join together.

The cloud becomes thicker and heavier. If the drops grow large enough, they fall to the ground as rain, snow, or hail.

So, clouds form because warm, moist air rises, cools down, and changes into tiny water droplets in the sky.