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How far away was that lightning?

Now that we are back in a rainier pattern with more frequent showers and thunderstorms, it’s time for a refresher about how to determine how far away a lightning strike is. Contrary to some people’s views, when you see lightning strike and then count the number of seconds until you hear the thunder, it takes 5 seconds for sound to travel one mile. So if you see lightning and then count ten seconds before you hear the thunder, the lightning stroke was 2 miles away. Not far! Here is an article from The Conversation which describes a little more about the calculation. If you can hear thunder roar, go indoors! Be safe and be smart. And if you watch a movie that shows thunder and then lightning, you know they should have hired a weather consultant because in the real world that doesn’t happen.

Source: David Selby/Commons Wikimedia