There’s no way to know where lightning will strike. It can, in fact, hit the same place twice. And, it’s even been recorded to strike up to 25 miles away from the actual storm.
So how do you defend yourself against something you can’t possibly predict? The key is to be smart in whatever situation you’re in.
The Science of Lightning
It’s common knowledge that lightning is electricity. But how does electricity come out of clouds?
Turns out, ice is to blame. As tiny chunks of ice tumble about in a storm cloud, they separate out into positively and negatively charged ions. The positive ones drift to the top of the clouds and the negative ones drift toward the bottom. Electricity — and lightning — occurs as electrons move between the two charges.
A similar process occurs between the moving storm cloud and the ground: the negatively charged cloud bottom causes a positive charge to build up on the ground, which in turn causes electricity — something like 100 million volts of it — to flow from the cloud to the ground.
As a general rule, lightning strikes tall things that conduct electricity. So first, stay away from tall things:
Don’t stand under tall trees, especially ones that stand alone.
- Stay away from fields, beaches, and other areas where everything around is shorter than you are.
- Stay off mountains during a storm — or at least get below the tree line.
Secondly, stay away from likely-to-be-struck materials. You can’t do much about conducting electricity yourself (the human body is pretty good at it), but you can at least make sure you’re not doing anything to enhance it:
- Get out of the water, including puddles. Even rubber boots won’t help much.
- Avoid touching anything made of or containing metal.
Of course, your best bet for staying safe is to find shelter. However, common outdoor shelters can be just as dangerous as no shelter in a lightning storm. When lightning hits something like a house or school, it travels through the wiring and pipes — which are grounded — and the dangerous current ends up going into the earth where it can’t do any harm. When lightning strikes something like a shed, however, you won’t have that protection.
So make sure you choose your shelter appropriately. You want something that’s fully enclosed — no picnic shelters or open garages — and has plumbing and wiring.
Being inside a plumbed and wired building is safer than being outside, but there are still some precautions to take. Remember lightning does travel through wires and pipes. So, avoid them. Stay away from sinks, toilets, and bath tubs as well as any electronic devices you’re likely to interact with, such as computers, video game consoles and corded phones.
When is it safe?
Stay inside until at least 30 minutes after the last flash of lightning or crash of thunder.
See what the experts have to say about lightning and lightning safety:
This article was orginally published in June 2009.