1. What is the Lightning Distance Calculation?

The lightning distance calculation estimates how far away a lightning strike occurred by measuring the time between seeing the lightning and hearing the thunder. Sound travels about 1 km in 3 seconds, while light travels almost instantaneously.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( Seconds \) — Time between lightning and thunder
• \( 3 \) — Sound travels 1 km in approximately 3 seconds

Explanation: Since light travels much faster than sound, the delay between seeing lightning and hearing thunder can be used to estimate distance.

3. Importance of Lightning Distance Calculation

Details: Knowing how far away lightning is helps assess storm danger. If the time between lightning and thunder is decreasing, the storm is approaching.

4. Using the Calculator

Tips: Count seconds between seeing lightning and hearing thunder, then enter that number. For accuracy, use a stopwatch or count "one-Mississippi" style.

5. Frequently Asked Questions (FAQ)

Q1: Why divide by 3?
A: Sound travels approximately 343 m/s (varies with temperature). 1 km takes about 2.91 seconds, so 3 is a practical rounded value.

Q2: How accurate is this method?
A: Reasonably accurate for distances under 20 km. Beyond that, sound may be refracted by atmospheric layers.

Q3: What if I don't hear thunder?
A: Lightning beyond about 25 km may be "heat lightning" where thunder isn't audible.

Q4: Does elevation affect the calculation?
A: Slightly - sound travels faster in warmer air, so high altitude may reduce the time slightly.

Q5: When should I seek shelter?
A: When lightning is within 10 km (30 seconds between flash and thunder).