Lightning is one of the most powerful and dangerous forces of nature on the planet. On a typical year it will kill more people then tornadoes or hurricanes which is amazing considering the destruction those storms do. With hurricanes and tornadoes there is often warning which can help save lives. With Lightning there are no early warning systems. Lightning is also capable of striking even when conditions appear safe like those of a cloudless day. The reason for this is that lightning can travel long distances without losing its potency since it is moving at the speed of light.
Lightning is caused by thunderstorms. The amount of energy in a single bolt of lightning is mind boggling. The heat generated from a lightning strike is hotter than the surface of the sun. Making them even more dangerous is that a single bolt can have up to a billion volts of electricity. High in the clouds frozen ice particles collide against each other creating an electrical charge. Electrons begin to form at the base of the clouds while protons form toward the tops. The ground which has a positive charge will attract the negative charges at the base of the cloud, creating a spark known as lightning. It does not have to be the ground which creates this spark as cloud to cloud lightning is very common as well.
Lightning is capable of traveling long distances. The reason that lighnting can strike on a cloudless day is that a storm miles away initiates the lightning and it simply travels. There have been cases of people being killed by lightning without a single cloud in the sky. Lightning has been known to travel 50 miles away from its original storm. As a result a clear sky in one area does not guarantee that lightning will not strike. Most lightning strikes travel less than 10 miles from its parent storm. So while the odds of getting struck on a cloudless day are not that high it has happened and it can in fact occur.
Lightning is a force that deserves respect and there are precautions people can take to minimize their risk of being struck. When thunderstorms are present go indoors and stay away from metal objects. Under trees in never a safe to place as they attract lightning strikes due to their height. Do not play in water when lightning storms are occurring. Stop activities and stay indoors until the threat has passed. Using common sense can save lives but there is no guaranteed protection from lightning.