Lightning, Thunder, and CloudsLightning is caused by the separation of positive and negative charged  electric particles in thunderclouds. It may take place through the interaction of water and ice in the clouds. Usually the positive charges accumulate in the upper portion of the cloud, and the negative particles accumulate near the base of the cloud several miles below. When the potential of the particles is greater than the resistance of the air between them, a bolt of lightning occurs. Lightning is a sudden atmospheric discharge of stored electricity. During the 1700's, experiments were conducted in a laboratory using a special type of jar (Leyden) to store static electricity. (When a storm rages, it seems like we are in a large Leyden jar full of static electricity ready to be released.)The start of a lightning bolt from a cloud or a high point on the ground is called a leader. Heating and expansion of the air along the top and bottom electric leader charges produces a shock wave known as thunder. Thunder always follows the flash of lightning. The sound of thunder travels at a speed of 1056 feet/second (a distance of one mile in 5 seconds). When lightning is seen, count the seconds until you hear the thunder; it is simple arithmetic to determine the storm's distance away. It is difficult to hear thunder more than 5 miles away. Thunderclouds are high and have a flattened anvil-shaped form that is usually very dark in color. These clouds are charged with electricity and produce lightning and thunder.  Usually spherical from approximately ½ inch to 40 inches in diameter. It lasts about 5 seconds and decays very rapidly, sometimes with a bang and can move horizontally at speeds of a few yards per second before dissipating. During a storm in 1978, an electrical phenomenon was seen over old Tampa bay. The light immediately exploded and radiated hundreds of fingers that seemed to be several hundred feet in diameter. The color was similar to what is seen in a large fireworks display from an aerial bomb. The shock waves shook the buildings, trees, and ground. Could this have been ball lightening (or what)?Sheet lightning: 
Lightning that remains within the cloud and does not strike earth.Forked lightning: 
Lightning that strikes the earth with capabilities to injure any living thing or damage objects that it hits. Lightning can occur during rainstorms, sandstorms, snowstorms, and within the clouds over erupting volcanoes. Benjamin Franklin, an American pioneer of influence, was fascinated by electricity. With his key, kite, and string made of hemp he proved that lightning consisted of electricity and through this experiment he invented the lightning rod. That device has saved many lives and property since its conception. REMEMBER! Keep a low profile in a storm, get out of the water if swimming, don't stand under trees, stay in the house, or if driving stay in your car until the storm is over; then your chances to watch the lightning, hear the thunder, and see the black clouds will be a sure thing until the next big storm.
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