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Estimating storm distance from the flash-to-bang gap
Count the gap between lightning and thunder to work out how far away a storm is.
- Time
- ⏱ 1 min
- Difficulty
- ◆ easy
What you need
- Watch or counting
How to do it
- See the flash and count the seconds until you hear thunder.
- Calculate seconds × 340 = distance in metres.
- Example: 9 seconds × 340 m/s ≈ 3.1 km.
Why it works
Light arrives almost instantly, while sound takes time. The speed of sound gives you the conversion.
Sources
This is where we found the tip. The badge above shows how well it is backed up.
- wetterdienst.de (opens in a new tab)
die Schallgeschwindigkeit von 340 m/s mit der Anzahl der Sekunden multipliziert, die zwischen Blitz und Donner vergehen.
