Did you know that thunder is the sound that lightning makes? That means you can’t have a thunderstorm without lightning. We don’t see lighting at the same time we hear thunder because light and sound travel at different speeds. Light travels much faster than sound, so we see lightning when it happens. The thunder is delayed because sound travels more slowly.
About 16 million thunderstorms occur worldwide each year, and the United States experiences more than 100,000 thunderstorms a year. In the Midwest, thunderstorms can occur year-round when weather conditions are favorable. They are most common in the spring and summer, however. About 10% of storms in the U.S. are severe, but remember that it’s never safe to be outside in a thunderstorm. When thunder roars, you should always head indoors.