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VERIFY: Can you determine how far away lightning is by counting?

When you see a bolt of lightning, do you immediately start counting to see how far off a storm is?

We've all heard about the rule, you see lightning, you start counting until you hear thunder, and then you divide the number of seconds by five and somehow you can figure out how far away you are from a lightning strike.

WMAZ set out to verify if this is in fact true, and if so how does it work?

To answer this question, we begin with the speed of sound, which depends specifically on what kind of medium the sound is traveling through.

For this question, we can use roughly 1,200 feet per second. This translates to roughly 4.4 seconds per mile.

To account for the time needed by our brain to process seeing a lightning strike, and to make the number a little more practical, five seconds per mile is a decent assumption.

Here's an example; say you see lightning and then count to five before you hear thunder.

You take that five seconds and divide by five to get one mile, which is roughly how far away the lightning is.

Take another example, say this time you count to 15. Divide 15 by five to get three. This means the lightning strike is roughly three miles away.

We can in fact verify that this is a roughly accurate way to determine how far away you are from a lightning strike.

Keep in mind that lightning can strike several miles away from thunderstorms.

As always, when thunder roars, go indoors.

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