By the numbers Thunder and lightning

100,000: Estimated number of thunderstorms that occur each year in the U.S.

10: Percentage classified as severe (hail, high winds or tornadoes)

20 million: Number of times lightning strikes the Earth each year

50,000: Temperature of lightning bolts, in degrees Fahrenheit

1 in 600,000: Your chance of being struck by lightning

Source: Various Web sites