Thunder can typically be heard up to about 10 miles (approximately 16 kilometers) away from a lightning strike. This distance varies depending on atmospheric conditions, but beyond roughly 10 to 20 kilometers, thunder usually becomes inaudible because the sound dissipates or bends away from the surface
. A common method to estimate how far away a thunderstorm is involves counting the seconds between seeing the lightning flash and hearing the thunder. Since sound travels roughly 1 mile every 5 seconds (or about 1 kilometer every 3 seconds), dividing the number of seconds by 5 gives the distance in miles, or dividing by 3 gives the distance in kilometers
. In summary:
- Thunder can be heard up to about 10 miles (16 km) away.
- To estimate distance:
- Distance in miles = seconds between lightning and thunder ÷ 5
- Distance in kilometers = seconds between lightning and thunder ÷ 3
- If you can hear thunder, you are generally within striking distance of the storm and should seek safety immediately
