StrikeDistance

StrikeDistance is a tool to estimate the distance to a lightning strike based on the time between seeing the lightning and hearing the thunder. The app can optionally use your current location to automatically check the current temperature, and a stopwatch is built in to help track the time. This is a recreation of one of my earliest programming projects as a student.

This app is intended for educational purposes only and should not be relied upon for safety decisions.

The speed of sound in air varies with temperature: v = 331.5 + 0.6T (where v is the speed of sound in meters per second and T is the ambient temperature in °C). The measured time between the lightning and thunder (in seconds) is combined with the speed of sound to estimate the distance in meters (d = vt). StrikeDistance can convert between units automatically, for example to show the result in miles.