According to NOAA, lightning strikes the Earth 100 times each second . There are about 45,000 thunderstorms daily and 16 million annually around the world. Lightning always accompanies the thunderstorm . These are nature's warnings that the thunderstorm is in its most violent stage. Tornadoes may also be associated with the thunderstorm.
Thunder is the sound produced by explosive expansion of air heated by a lightning strike.
When lightning is close by, the thunder sounds like a sharp crack . This can be done by counting the number of seconds between the lightning and thunder and dividing by five. Equate thunder with lightning , even if lightning is not visible where you are. If you can hear thunder, you are close enough to be struck by lightning. Even if you can't hear thunder, you might still be at risk.