To estimate the number of miles you are from a thunderstorm, count the number of seconds between a flash of lightning and the next clap of thunder, then divide this number by five. From 1959 through 1997, there were 550 reported lightning-related injuries. Lightning-strike victims carry no electrical charge and should be attended to immediately. Lightning results from the buildup and discharge of electrical energy between positively and negatively charged areas. The action of rising and descending air within a thunderstorm separates positive and negative charges.
Most lightning occurs within the cloud or between cloud and ground.
When one channel nears an object on the ground, a powerful surge of electricity travels from the ground upward to the cloud producing the visible lightning strike. The average flash of lightning could light a 100-watt light bulb for more than three months. The air near a lightning strike is heated to 50,000 degrees F - hotter than the surface of the sun. The rapid heating and cooling of the air near the lightning channel causes a shock wave that results in thunder. Heat lightning actually is lightning from a thunderstorm too far away for thunder to be heard.