Lightning travels at approximately 186,000 miles per second.
This incredible speed is the speed of light. It is crucial to distinguish this from the speed of thunder, which is the sound produced by the rapid heating of air around the lightning channel. Thunder travels much slower, at roughly 1 mile every 5 seconds at sea level (the speed of sound).
Here's a breakdown:
- Lightning Speed: Approximately 186,000 miles per second (speed of light)
- Thunder Speed: Approximately 1 mile per 5 seconds (speed of sound at sea level)
The vast difference in speed is why you see lightning almost instantly but hear the thunder seconds later. The delay between seeing the flash and hearing the thunder allows you to estimate how far away the lightning strike was. For every 5 seconds of delay, the lightning is approximately 1 mile away.
