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Thunderstorms and Lightning
Heavy rains, strong winds, flash floods, hail, lightning and tornadoes can all accompany a severe thunderstorm. Southern and central states get frequent thunderstorms, which can form singly or in clusters or lines.

Nearly 1,800 thunderstorms are in progress somewhere in the world at any given moment. The U.S. gets 100,000 thunderstorms a year, which spawn about a thousand tornadoes. Large hail causes damage to property and crops costing about a billion dollars every year. Fires, often caused by lightning, are the most frequent of all natural disasters.

Lightning, found in all thunderstorms, is an electrical discharge within the clouds or between the clouds and the ground. Thunder is a result of rapid heating and cooling of the air near a lightning bolt, which can reach temperatures near 50,000 degrees Fahrenheit in a split second. Anytime you can hear thunder, you are in danger from lightning.

As many as 100 Americans are hit and killed by lightning every year. Lightning can strike the same place twice, and in fact strikes several times in one place during one discharge. Because of its electrical nature, lightning is especially attracted to good conductors such as metal objects like wire fences, umbrellas, golf clubs, fishing rods, tractors, bicycles, and tools.

The National Weather Service issues a severe thunderstorm watch when conditions indicate that a storm with winds of at least 58 mph or hail larger than 3/4-inch is likely to develop. A severe thunderstorm warning indicates that such a storm appears on radar or has been sighted.

Do not use wired telephones, televisions or electrical devices during a severe thunderstorm because lightning can follow the wires. Metal pipes and water can also conduct lightning, so avoid swimming pools, bathtubs and water faucets. Never approach nor touch downed utility wires, and don't seek shelter under a tree in an open area. If driving, pull off onto the shoulder away from trees, turn on the flashers and stay in the car.

To reduce thunderstorm damage, remove dead limbs on trees, secure outdoor objects that can be blown around, and consider installing electrical surge protection devices and lightning rods and purchasing flood insurance. Keep gutters clean and be sure storm water will run away from building foundations. Provide shelter for pets and livestock. Keep emergency supplies on hand.