NimbusLab
All toolsCloud & Phenomena Identification

Thunderstorm Distance Calculator

Tap when you see the flash and again when you hear the thunder. The tool reports distance in km and miles.

Live tool

Sound speed at 20°C: 343.4 m/s
Distance
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Tap Flash when you see lightning, then Thunder when you hear it.

Introduction & principle

Sound travels at roughly 343 m/s in dry air at 20 °C. Multiplying the flash-to-thunder delay by the speed of sound gives the storm distance. The tool adjusts for the temperature you enter.

Tool advantage

No mainstream app gives a quick stopwatch-style distance read. This tool is built for that single observation.

Detailed usage guide
  1. 1Enter the ambient temperature for an accurate sound-speed adjustment.
  2. 2Press FLASH when you see lightning.
  3. 3Press THUNDER when you hear the boom.
  4. 4Read the distance and the implied storm-cell direction.
Common problems & FAQ

Is the 3-second rule accurate?

It is an approximation. The tool uses the exact temperature-corrected speed of sound for better accuracy.

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