National Weather Service United States Department of Commerce


lightning strike

Lightning results from the buildup and discharge of electrical energy between positive and negative charges. The air near a lightning strike is heated to 50,000 degrees Fahrenheit, which is hotter than the surface of the sun. The rapid heating and cooling of air near the lightning channel causes a shock wave which results in thunder.

Lightning will normally strike the highest object in an area. The highest object may be a tall tree, a boat on a lake, an antenna or a person standing in an open field. Lightning is also responsible for fires which have resulted in several hundred million dollars a year in damage and the loss of 2 million acres of forest.

Lightning is the one of the leading causes of weather-related deaths during an average year. Most casualties occur during the summer months in the afternoon and early evening. Most lightning deaths and injuries occur when people are caught outdoors. A persons chance of being struck by lightning is approximately 1 in 600,000, but is greatly reduced by following safety precautions.