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Mesoscale

Who Said Lightning Doesn't Strike The Same Place Twice?

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Its an urban myth that it doesnt strike the same place twice.

Agreed, After the initial strike the probability does drop due to the discharge of the area. However energy can build quickly and cause the same strike again.

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My parents' house was struck three times in 10 years (3 August 1994, 26 September 1999, 17 June 2003), and not in a particularly thunder-prone location, so I've known it was a myth for some time.

Large buildings like the Empire State Building have traditionally been hit many times during an individual significant thunderstorm- indeed, part of the idea of lightning rods is to encourage lightning to strike repeatedly in harmless places.

I imagine it must be quite unerving seeing lightning strike your house twice in the space of 30 seconds like on that footage though!

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Just to be pedantic, it always strikes twice due to the strokes in each bolt :good:

I also like to watch my local landmark:

http://en.wikipedia.org/wiki/Jubilee_Tower

In the most active lightning storms and count how many times it is hit, the most me and my friends counted was 16 separate hits during a severe storm one evening in 1995.

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Wow!

But why oh why is the guy wearing sandals and socks!!!

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But why oh why is the guy wearing sandals and socks!!!

I know, what kind of fashion statement is that? :)

A popular myth is that lightning cannot strike the same place twice, but nothing could be further from the truth. Lightning does, can and will strike the same exact place more than once. It doesn’t have a memory, and if an object has been struck once, it is no less likely to be struck a second time. If you don’t believe me, just ask some of the employees at Cape Canaveral in Florida. The shuttle launch pad gets hit time and time again, sometimes more than once in the same storm. How about the Empire State Building in New York city which gets struck by lightning about 25 times each year. Even Roy Sullivan was struck by lightning 7 times!

The truth of it is, lightning is simply trying to balance a charge separation; positive and negative. Very tall objects such as skyscrapers, mountains and radio towers are more likely to be struck because they narrow the gap between the charge separation of the ground below and the oppositely charge cloud above. When the charge builds up enough to overcome the resistance of the air, the opposite charge will rush upwards along the structure more easily than through the air and as a result the gap between the two charges is lessened increasing the chance of a strike.

Ironically, objects that are taller than their surroundings aren’t always the lightning’s first choice. Lightning may miss a 80 foot tree and instead strike the rooftop of a house right next to it. If the tallest objects were always struck then every tree, telephone pole and house on the open prairie would have the unfortunate pleasure of being struck. Lightning rods would always work and predicting where a lightning bolt strikes would be a very simple science. Millions of dollars in damages could be prevented each year and harnessing the power of lightning would be a very simple task.

The fact is, objects closer to the ground play a much smaller role in determining what a lightning bolt is going to strike because lightning doesn’t know what it’s going to make contact with until the last 50 to 100 feet. That is to say, lightning doesn’t know at 50,000 feet that its going to strike your neighbors satellite dish. Lightning zig-zags down to the ground by forming “step-leadersâ€, re-evaluating at each step where it’s going next. Sometimes left, sometimes right, sometimes down, sometimes up. Once the step-leader approaches a grounded object, a “streamer†composed of the opposite charge shoots upwards. One can shoot up from a telephone pole, a tree, a car or all three simultaneously. Whichever streamer connects with the descending step leader first will complete the circuit and trigger a mass rush of electricity creating a lightning bolt. But the taller object might not be the closest target and it might not throw up as tall a streamer. The tallest object may be just a 100 feet further away than a shorter one and the shorter one will get hit because its streamer made contact with the step leader first.

While watching a thunderstorm, you might of noticed lightning sometimes looks like it’s pulsating or flashing several times very quickly. Sometimes all the charge doesn’t dissipate in one flash over. The electric current will pulse down the channel hitting the same place several times in quick succession. In essence, lightning is hitting the same place many times in a row in a very short amount of time.

But just because an object is hit once, doesn’t not make it immune from being struck again. If a storm is in the area, an object has the same probability of being hit a second time.

www.weatherimagery.com/blog

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In 2003 the teliphone pole outside got struck everyones phone died but my tv got it instead... claimed on the insureance... it did that twice once in 2006

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