"When thunder roars, go indoors, and stay in there for 30 minutes after you hear the last thunder clap," said Susan Buchanan, spokeswoman for the National Weather Service in Silver Spring, Md., and a member of the agency's lightning safety team.
"Lightning is unpredictable," she added. "There's no safe place outdoors in a thunderstorm. If you remain outdoors during a thunderstorm, you are taking a gamble that you won't become one of the statistics."
And those statistics are staggering.
Every year, according to the National Weather Service, the Earth experiences 16 million thunderstorms. That amounts to an average of 1,800 storms happening at any given moment. Over the course of a year, 25 million bolts strike the ground, usually during thunderstorms but also during intense forest fires, heavy snowstorms, volcanic eruptions, nuclear detonations and large hurricanes.
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Lightning kills an average of 55 people every year, Buchanan said, but it hits and severely injures hundreds more. According to calculations on NOAA's National Severe Storms Laboratory website, there is a one in 3,000 chance of getting killed or injured by lightning in your lifetime, assuming an average life span of 80 years. The chances of lightning hurting someone close to you is one in 300.