Hail forms inside clouds when water droplets rise into air that’s below freezing, and freeze. In a thunderstorm, water droplets are lifted by an updraft to become ice. The longer the ice stays in the freezing air, the more layers of ice...

This live-action video program is about tornadoes. The program is designed to reinforce and support a student's comprehension and retention of the term through use of video footage, photographs, diagrams and colorful, animated graphics...

The atmosphere is dynamic and forever changing to maintain balance. The ingredients of air, sunlight and water allow life to exist on Earth, but they also generate calm scenes like rainbows, as a tornado ends. All storms move moisture,...

The atmosphere is dynamic and forever changing to maintain balance. The ingredients of air, sunlight and water allow life to exist on Earth, but they also generate calm scenes like rainbows, as a tornado ends. All storms move moisture,...

A flash of lightning, and a rumble of thunder. But what exactly are these spectacular occurrences? In 1752, Benjamin Franklin discovered that lightning was caused by powerful electrical discharges in clouds. He wasn’t the first person to...

Clouds can be strange or odd, with texture that might remind you of grapes or upside-down bubbles. Often around thunderstorms, you might spot mammatus clouds. They form when cloud water droplets or ice crystals sink into dry air,...

All thunderstorms create hazards of lightning. Some thunderstorms result in flash flooding, large hail, damaging wind or a tornado. See how to prepare for these threats at school, at home, or outside. Understand the difference between a...

The atmosphere is dynamic and forever changing to maintain balance. The ingredients of air, sunlight and water allow life to exist on Earth, but they also generate calm scenes like rainbows, as a tornado ends. All storms move moisture,...

The atmosphere is dynamic and forever changing to maintain balance. The ingredients of air, sunlight and water allow life to exist on Earth, but they also generate calm scenes like rainbows, as a tornado ends. All storms move moisture,...

When lightning strikes trees and other tall objects, it doesn't just stop. It may run along or just beneath the ground where the intense heat turns soil moisture into steam that blows the soil outward, to instantly create what is called...

Lightning is spectacular, from a distance. It's nature's way of transferring electricity within the sky, or between the sky and the ground. When lightning is nearby, it is a threat to safety. People are struck by lightning, in many cases...

This video explains the science behind lightning and its dangers. It discusses how charges build up in storm clouds, leading to an electrical discharge between the cloud and the ground. This video is part of the 9-part series, Electricity.

The atmosphere is dynamic and forever changing to maintain balance. The ingredients of air, sunlight and water allow life to exist on Earth, but they also generate calm scenes like rainbows, as a tornado ends. All storms move moisture,...