Posted: Jun 27, 2014 9:32 AM by Meteorologist Josh Eachus
Updated: Jun 27, 2014 9:32 AM
Stats, strikes and safety--lightning safety awareness is wrapping up and the details discussed provide information that we can use to guard against one of nature's top killers. Still, myths surround the deadly electrical current and understanding the truth about lightning could be life-saving knowledge.
Since 1951 the United States has averaged 51 reported lightning fatalities per year. Only about 10% of people struck by lightning are killed, leaving the others with varying degrees of disability.
Given an estimated 2014 U.S. population of 318,000,000, the National Weather Service calculates a single person's odds of being struck by lightning in a given year at 1 in 1.9 million. Assuming an 80 year lifespan, you have a 1 in 12,000 chance of being struck in your lifetime and there is a 1 in 1,200 chance that somebody you know will be struck.
Lightning is an electrical current, and scientifically speaking, doesn't actually have a temperature. However, the resistance created by objects through which it passes, does generate heat. Poor conductors of electricity, like air, can heat to 50,000°F as lightning passes through. This is 5 times hotter than the surface of the sun. The rapid warm-up provides the air column no time to expand to the appropriate pressure and thus it explodes intensely, producing the crack or rumble of thunder. As lightning strikes trees, the water within them may be super-heated in a split second, causing the tree to blast apart.
A typical lightning flash is about 300 million volts and 30,000 amps. Most lights in your home are 120 volts and 15 amps.
Especially during summer nights in South Louisiana, distant thunderstorms are often mistaken for "heat lightning." There is no such thing as "heat lightning;" a lightning producing storm is simply too far away to see the bolt or hear thunder.
While a car is a relatively safe place to be during a thunderstorm, rubber tires DO NOT make it immune to lightning strikes. Lightning can strike a car as any other outdoor object, typically hitting the antenna or outer metal shell. The electrical current then passes over the surrounding metal, through the rubber tires and into the ground. In many cases, cars are partially or fully destroyed after a lightning strike. With the windows up, people inside of a car struck by lightning are protected though.
Similar to cars, aircraft are not immune to but are protected from lightning strikes. They are designed to have conducting paths for the electrical currents produced by lightning. Planes may actually initiate lightning as they pass through the ambient electrical fields of a storm cloud. Most commercial planes avoid thunderstorms though because a strike can be damaging and costly.
Lightning strikes water often and it can kill living creatures on the ground, so what about fish? Before a lightning strike, a charge builds up along the water's surface and most energy is discharged there. Fish swim a few feet beneath the surface and typically go unharmed.
The phrase ‘lightning never strikes twice' is a misnomer. Lightning often strikes the same place multiple times-especially taller outdoor objects. The Empire State Building is hit nearly 100 times per year. The WBRZ TV tower is another frequent target.
Lightning strike victims are NOT electrified, and it is NOT unsafe to touch them. In fact, you should touch them, providing first aid and CPR if needed.
Wearing or holding metal DOES NOT attract lightning. Height, shape and isolation of an object are the factors that determine the likelihood of lightning striking an object. Metal does conduct lightning though, so it is a good idea to avoid metal objects in a thunderstorm.
To find out how far away lightning is, after seeing the flash or bolt, count the seconds until you hear thunder and then divide by 5.
As lightning safety awareness week concludes, feel free to visit the additional stories we've posted (linked to this story) for further information or check the National Weather Service lightning safety page.
You can get forecasts from Meteorologist Josh Eachus weekdays on 2une-In from 5-7am and News 2 at Noon from 12-1pm. Additionally, you can get the fastest and latest forecasts and weather news by checking in with wbrz.com/weather, liking Josh on Facebook and following him on Twitter.
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