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Are lightning strikes becoming more common?

An image of lightning from NOAA's National Severe Storms Laboratory Collection.

NOAA Photo Library; OAR/ERL/National Severe Storms Laboratory (NSSL)

There have been 16 deaths from lightning in the U.S. so far this year. With seven of those fatalities occurring in the month of July -- including three in the past week -- it might seem as though lightning strikes are suddenly becoming more common.

But over the past decade, the number of injuries and deaths caused by lightning have actually gone down, according to John Jensenius, a lightning specialist for the National Weather Service.

"The number of fatalities has decreased because of more awareness," he told CBS News. The National Weather Service began a lightning safety campaign in 2001, including the first national Lightning Safety Awareness Week. Prior to that, the annual number of lightning fatalities was double what it is today.

Getting struck by lightning remains an extremely rare occurrence. Last year, it was blamed for 27 deaths across the country.

So why does it seem like the number of incidents has surged in recent days? "July is peak in lightning fatalities and peak in lightning across the U.S," Jensenius said.

In a January 2016 analysis of lightning deaths in the U.S. over the past nine years, Jensenius wrote that the summer months are peak time for lightning as well as the peak months for outdoor activities. "As a result, more than 70 percent of the lightning deaths occurred in the months of June, July, and August, with Saturdays and Sundays having slightly more deaths than other days of the week," he wrote.

Fishing was the riskiest activity for lightning strikes, with 33 deaths from 2006 to 2015. People at the beach or on camping trips were also more vulnerable.

How lightning works

As Ben Franklin famously demonstrated, lightning is a form of electricity. Thunderclouds are made up of cold air that forms ice crystals and warm air that forms water droplets. During a storm, these crystals and water droplets collide to create an electrical charge in the clouds. The charges separate with the positive charges or protons at the top of the cloud and the negative charges or electrons at the bottom. When the negative charge gets strong enough, energy is released from the cloud and goes through the air to a place with an opposite charge, such as the ground or a tree or even a person.

And lightning is extremely hot. According to the National Weather Service, "As lightning passes through air, it can heat the air to 50,000 degrees Fahrenheit (about 5 times hotter than the surface of the sun)."

Lightning is very common and strikes somewhere in the United States nearly 25 million times per year. Although summer months are prime season for lightning, people can get struck at any time of the year.

Interestingly enough, Jensenius noted that 80 percent of lightning fatalities occur in men. He suggested several possible explanations, including that men are unaware of all the dangers associated with lightning, are more likely to be in vulnerable outdoor situations, or are unwilling to be inconvenienced by the threat of lightning.

Zapping lightning myths

Despite efforts to raise awareness about lightning strikes, many myths about the dangerous phenomenon persist.

"People are taking chances and getting needlessly struck or killed," Jensenius said.

Daniel Batcheldor, head of the physics department at Florida Institute of Technology, said a lot of people mistakenly believe that they are safe as long as a thunderstorm is five miles away. But he told CBS News that was wrong: "Lightning can travel huge distances and can cause a strike many many miles away from where a storm is taking place." He added, "A blue sky doesn't mean that you're safe."

Some people also believe that they're safe outside during a thunderstorm if they are wearing rubber-soled shoes. While rubber is an electricity insulator, it can't fully protect you from a bolt of lighting, which can burn right through with its 30,000 amps of charge, 100 million volts of electric potential and temperature of 50,000 degrees Fahrenheit.

So Batcheldor said don't rely on your shoes. He added, "Not everyone knows what their shoes are made of anyway."

What to do in a thunderstorm

There is no safe place outside during a thunderstorm so the best thing to do is to get indoors as quickly as possible. If you are outside, Jensenius said to avoid tall objects like trees or poles because lightning can easily strike them. He also said to avoid open spaces, which can increase the possibility of a direct lightning strike.

His rule of thumb: "When thunder roars, go indoors."

Once indoors, stay off of electronic devices such as corded phones and computers because if a house gets struck by lightning, the charge can travel through the wiring system and cause a fire. You're also advised to stay away from windows and doors.

And wait until 30 minutes after a storm passes before going back outside because a charge can linger in the air.

"We should always be paying attention to lightning because it is a potentially deadly killer," Jensenius said.