Cumulonimbus Clouds: Lesson for Kids

Instructor: Diane Sieverson

Diane has taught all subjects at the elementary level, was the principal of a K-8 private school and has a master's degree in Measurement and Evaluation.

You may have noticed that some clouds look different from others. This lesson will teach you about cumulonimbus clouds, what they look like and what kind of weather to look for when they appear in the sky over your town.

What Is a Cumulonimbus Cloud?

A big, bright bolt of lightning streaks across the sky. A few seconds later, you hear the rumble and crash of thunder as it shakes the windows in your house. The sky is dark and the rain is pouring down. Those gloomy clouds keeping you from playing outside and having fun are called cumulonimbus clouds.

Cumulonimbus clouds are large, tall clouds that are dark on the bottom and usually produce rain and thunderstorms. In fact, they are sometimes called thunderstorm clouds, but they can also bring different kinds of weather, including hail and snow showers, which might even get you out of school for a snow day!

Tall cumulonimbus cloud with dark bottom
Tall Cumulonimbus Cloud with Dark Bottom

Cumulonimbus clouds also form during hurricanes and can become tornadoes, so it's good to be on the lookout for bad weather if you see them in the sky.

More About Cumulonimbus Clouds

The word cumulonimbus is formed from two words. Cumulus means 'pile' in Latin, and nimbus means 'rain cloud.' These describe a cumulonimbus cloud perfectly, because it grows up vertically like a billowy pile, and these clouds usually bring rain or other wet weather.

A cumulonimbus cloud can grow more than eleven miles high into the sky. The top of the cloud sometimes gets blown by strong winds and has a flat top, like a table. That flat top is called an anvil, because it looks like the flat metal block called an anvil that's used to hammer metal.

Cumulonimbus cloud with anvil
Cumulonimbus Cloud with Anvil

A cumulonimbus cloud is made of very tiny drops of water. But because these clouds grow so high in the sky, the drops of water freeze higher in the cloud as the temperatures get colder. This makes the outline of the top of the cloud look a little fuzzy, without clear edges.

Is it Actually a Cumulonimbus Cloud?

You've learned about cumulonimbus clouds and what kind of weather they bring, but they can still be tricky to identify. In order to be sure that you're really looking at a cumulonimbus cloud, look for these features:

  • The cloud is very dark on the bottom.
  • The cloud has grown very high in the sky, like a pile.
  • The cloud has a flat top.
  • There is lightning and thunder.
  • There is sudden, hard rain, hail or snow shower.
  • The top of the cloud looks a little fuzzy.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account