How does a cloud form? When is the best time to see a rainbow in the sky? Why do ice cubes shrink in the freezer? The answers to these questions all involve water. So do the reasons why we have rain and snow. To understand weather, we have to know what happens to water at different temperatures, on the ground and in the air. In this fact-packed book, discover what happens when water changes from a liquid into a gas or a solid, and much more.

Why does the wind blow? What does air pressure have to do with a thunderstorm? Why is a mountaintop snowy while the valley below is warm? The answers to these questions all involve the layer of air surrounding Earth-the atmosphere. Earth's atmosphere is always in motion. It moves clouds, storms, and warm and cold air from one part of the planet to another. In this fact-packed book, discover how the ever-changing atmosphere determines weather around...