In a thunder storm, lightning always comes first, because the speed of light is faster than the speed of sound. There's a trick commonly used to find how far away you are from the lightning during a storm. When you see the flash of lightning, you begin to count. You continue counting and stop when you hear the thunder. Let's say you count to ten. Then you are supposedly ten miles away from the lightning. The common misconception is that each second represents one mile of distance between you and the storm. According to the National Lightning Safety Institute, "Light from lightning travels at the speed of 186,000 miles per second (300,000 km/second), arriving at the observer in about 10 microseconds when the strike point is 1.85 miles (3 km) away. The sound wave, at an air temperature of 68° F (20° C) and atmospheric pressure of 29.92 in of mercury or 1,013.25 millibars, arrives more slowly in about 10 seconds." In this scenario of common storm conditions, every five seconds represents 1 mile of distance between you and the storm. Looks like we were closer to getting struck than we thought we were!