Everyone has been in a storm and knows how dangerous lightning can be. But how safe are you in a thunderstorm? Here is a handy chart provided by the National Oceanic and Atmospheric Administration that shows you just how far that potentially spine-zapping lighting is from your position.
To estimate the distance between you and a lightning flash, use the “Flash to Bang” method: If you observe lightning, count the number of seconds until you hear thunder. Divide the number of seconds by five to get the distance in miles.
Example: If you see lightning and it takes 10 seconds before you hear the thunder, then the lightning is 2 miles away from you (10 divided by 5 = 2 miles).
If Thunder is heard | The Lightning is… |
5 seconds after a Flash | 1 mile away |
10 seconds after a Flash | 2 miles away |
15 seconds after a Flash | 3 miles away |
20 seconds after a Flash | 4 miles away |
25 seconds after a Flash | 5 miles away |
30 seconds after a Flash | 6 miles away |
35 seconds after a Flash | 7 miles away |
40 seconds after a Flash | 8 miles away |
Get to a safe location if the time between the lightning flash and the rumble of thunder is 30 seconds or less.
[Via the NOAA]