What Happens When Lightning Strikes?
Everyday STEM Trends in STEMDate June 10, 2025
Est. Reading Time 3 mins
Have you ever looked outside during a storm to see the sky light up with a flash before the loud crack of thunder? Then you’ve probably seen stunning bolts of light called lightning. But what exactly is lightning? And how can we stay safe from extreme weather? Keep reading to uncover tips, tricks and interesting facts about this extreme weather phenomenon!
What Causes Lightning?
Lightning appears during thunderstorms as a big electrical spark. We see a bright flash and stringy bolts of light that can be miles long! The water inside a cloud contains both positive and negative charges – when one kind of charge builds up inside the cloud, the excess charges are attracted to the opposite charge on the ground. As the charges grow in strength, they leave the cloud and travel toward the ground where they are met on their way down with an opposite charge rising from the ground. The two collide in an electric flash of lightning. These flashes can go from Earth’s atmosphere to the ground, start at the ground and go up to the atmosphere or jump between clouds.
While the Earth can have millions of lightning strikes a day, just one spark of lightning has the power to keep a 100-watt light bulb lit up for three months straight!
Safety Tips and Tricks
For some people and pets, lightning can ruffle up anxiety. While such extreme weather can be dangerous, the National Weather Service shares safety information to keep in mind the next time you encounter a thunderstorm. Remember, the safest place to be is inside!
- When you hear thunder, move indoors to a safe shelter like an enclosed building or vehicle.
- You don’t want to be in direct contact with metal or electrical equipment.
- Keep away from windows.
If there is no shelter nearby, be sure to stay off elevated areas, avoid sheltering under isolated trees and move away from bodies of water or objects that could conduct electricity.
Bring Weather Science to Life
Another way to ease weather worries is to understand what is happening and have a plan in place if you encounter unexpected weather phenomena. Start by considering local cases of extreme weather and how innovative humans have used these as invention inspiration to make our lives safer. Then, check out this STEM activity to brainstorm the next great device to navigate weather and learn how National Inventors Hall of Fame® Inductee Mary Anderson responded to wet conditions by creating the first effective windshield-clearing device. Finally, discuss a plan with your family for what to do in the event of extreme weather near you.
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