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When. Lightning. Strikes!. On July 2, 1992, Hernan Cortes was lucky enough to capture a lightning strike on his home video. “It is one of those rare times that the destructive forces of lightning has been captured on video tape.” -Tom Skilling, WGN, Channel 9.
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On July 2, 1992, Hernan Cortes was lucky enough to capture a lightning strike on his home video. “It is one of those rare times that the destructive forces of lightning has been captured on video tape.” -Tom Skilling, WGN, Channel 9 I have been given permission to use images from Hernan’s website, www.dastrike.com, to show you the details of a lightning strike.
Lightning begins as a buildup of static charges, usually in a thunderstorm. The bottom of the cloud develops a negative (-) charge and the ground develops a positive (+) charge. These charges remain separated by the space between the cloud and the ground.
The charges must build up enough potential to jump the gap between the cloud and the ground.
A lightning strike is much like a huge static discharge. It is similar to the shock you get when you shuffle in sock feet across the carpet and then touch a metal doorknob, only much bigger.
Have you ever noticed what kinds of things lightning strikes? Lightning usually strikes objects that offer the shortest path from the cloud to the ground. It also strikes where the built-up charge is the strongest. This means it can strike anything from a house, to a tower, to a tree, to a person.
Before lightning can strike, there must be a connection made. An initial “string” of electrical charge comes up from the ground, searching for a connecting “string” from the sky. The one starting on the ground is called a LEADER.
Here is an image of a leader. Notice how it extends upward from the tree to the sky. …YET… This is NOT a lightning strike…
The “string” that comes from the cloud is called a TRAILER. It forms the path between the cloud and the ground when it connects with a leader.
A LIGHTNING STRIKE! The result of a connecting leader and trailer is…
Watch the following series of pictures to see several lightning strikes in slow motion…
To figure out how far away lightning is… Start counting seconds after you see the flash. Keep counting until you hear the thunder. For every 5 seconds you counted, the lightning is 1 mile away.
Remember, when lightning is present… • Find shelter indoors or in a closed vehicle • DO NOT seek shelter under trees or tall objects • Get out of swimming pools and off lakes • If you are stranded outside, crouch low, hugging your knees. Limit how much of your body touches the ground.