Lightning - understanding it can save your Life

Lightning claims more victims each year than tornadoes and hurricanes. An average of 73 people are killed each year and hundreds more injured. We don't notice it as much because it usually kills or injures one person at a time, nonetheless, it is deadly. A person can be struck by lightning when a thunderstorm is ten miles away and the skies are blue.

Thunderstorms tend to form in the afternoons. Moist, unstable updrafts and downdrafts form in cumulonimbus clouds, causing collisions of rain and ice particles. The collisions cause electrical charges to separate. Positive charges go high and negative charges hang low in the cloud. The result is an electrical imbalance both within the cloud and between the cloud and ground. Nature tries to restore balance with lightning.

The average lightning flash has enough energy to power a one hundred light bulb for three months. Around the lightning bolt, the air is heated to nearly 50,000 degrees F (27,760 C,) hotter than the surface of the Sun! This extreme heat causes the air to suddenly expand as thunder.

Most lightning flashes occur within the cloud itself and never reach the ground. The lightning which hits people is a cloud to ground flash. As the negative charge from the cloud nears the ground, positive charges surge upwards from tall objects like trees, houses, telephone poles and tragically, sometimes people. When the two charges connect, a lightning flash occurs.

In the US, it is estimated that 22 million lightning flashes strike the ground each year. Lightning frequency generally decreases from the southeast to the northwest, but there are pockets of intensity around the Rocky Mountains. Although summer is when most lightning occurs, it can also strike during the winter in a rare thunder snowstorm.

A common saying is that lightning never strikes the same place twice. If the ground were flat all over, there would be some truth to this. The reality though is that the ground isn't flat and lightning is attracted to taller objects. In fact, tall structures such as the Empire State Building get hit several times in a single storm.

I often hear people referring to heat lightning. Generally they are talking about a distant flash when they hear no accompanying thunder. The truth is, there is no such thing as heat lightning. What they are seeing is a lightning flash, often reflected through clouds, that is so distant they cannot hear the thunder.

The best way to avoid being hit by lightning is to follow the National Weather Service's "30/30" rule. When you see lightning, count the time until thunder is heard. If it is 30 seconds or less, seek shelter immediately and stay there for at least 30 minutes after the last rumble of thunder is heard.

Shelter should preferably be a solid structure, not a covered picnic area, though that's better than nothing. Cars are also safe if they do not have a convertible roof. And stay off the phone! The leading cause of lightning injuries inside the house is using the phone.

If your hair stands up in a storm, it's likely a sign that positive charges are rising through you, reaching toward the negatively charged part of the storm. Get indoors immediately!

If you cannot find shelter, make yourself as small a target as possible. Never stand near tall trees, metal fences, power lines or water. Squat on the ground and put your hands behind your head, not on the ground! It is not true that rubber soled shoes will protect you from lightning, use common sense instead.

For all the fright and damages lightning causes, it may also be the very reason we exist. Scientists think the immense heat and energy from lightning may have played a part in the evolution of the earliest living organisms, some of which eventually became humans.

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The Solar System