The Distance of a Lightning Strike

The Distance of a Lightning StrikeLightning, thunder, hail, and torrential rain: a beautiful afternoon to sit snuggled together inside our warm, dry house as we watch the storm pass by.


The lightning is beautiful as it arches and flashes through the sky.  It’s also close enough that it’s making our house shake.


As we watched it from inside (this is not the weather for being outside), I reminded my boys how to calculate our distance from a lightning strike.  Because light travels faster than sound, we can calculate the distance by using the following formula:


  1. Watch for a lightning flash.
  2. Count the number of seconds between the lightning flash and the rumbling of the thunder.
  3. Take the number of seconds between flash and sound and divide it by 5.
  4. The result is the number of miles you were from the lightning strike.


For example, if you see a lightning flash and then count 15 seconds before you hear the thunder rumbling, you’ll know that the lightning strike was 3 miles away.


Now you can know how to calculate your distance from a lightning strike.  This is helpful information if you’re outside and notice a thunderstorm forming or approaching.  It’s also simple, fun science.



Do you enjoy watching thunderstorms?

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