Have you ever wondered why tornadoes twist? Or what makes thunder rumble? Scientists who study weather, called meteorologists, can help us understand.

The sun, the air, humidity (or water in the air) and wind cause the weather. Together, they help spread the sun’s heat around the world. Without weather, areas around the equator would get much hotter, while the north and south poles would get colder. After a while, Earth would no longer be a pleasant place to live!

Most of the time, weather is simple – rain, snow or sun. But sometimes the weather does exciting things. A tornado happens when two types of air, like dry air and moist air, come together. If the speed and direction of the winds are just right, they may spin the storm like a top. Thunder happens after lightning during a storm. The lightning bolt heats up the air so fast that it breaks the speed of sound.

You can learn a lot more about the weather at skydiary.com/kids.* And the next time you see a storm coming, remember that your savings account is the perfect place to save for a rainy day.

* Web site is provided for information only. No endorsement is implied.