Weather field note
Sky's stopwatch
Counting the Storm
You can guess how far away a storm is by counting the seconds between a flash of lightning and its rumble of thunder.
Let's look closer
Why does thunder always come after lightning?
ight travels so fast that we see lightning almost the instant it happens. Sound travels much slower, so thunder takes extra seconds to reach our ears. Counting those seconds and dividing by five tells you roughly how many miles away the storm is.
Look for this
Explorer clue
During a safe, distant storm, count slowly from the flash until you hear the rumble, then try again on the next flash to see if the storm is coming closer or moving away.
Your turn to wonder
Curiosity question
If you could measure distance with your own ears, what else might you want to listen for?