D.C. lightning strike killed 3 people outside White House. Here's what you need to know to stay safe.

·5 min read

A lightning strike that killed three people last week outside the White House has drawn attention to the dangers of being outside during thunderstorms, and experts are warning of the importance of lightning safety.

The three deaths – of a 29-year-old man and a couple in their 70s celebrating their wedding anniversary – are among 13 lightning fatalities this year, according to the National Oceanic and Atmospheric Administration.

There are about 25 million lightning strikes across the U.S. each year, said Aaron Treadway, a severe-storm services coordinator for the National Weather Service. Of those, about 3,000 strike people each year, and about 20 people die. Many more are severely injured, he said.

Survivors often suffer lifelong health conditions, including chronic pain, neurological disabilities and depression because lightning damages the body's central nervous system, said Treadway, who is based in Norman, Oklahoma.

Here's what you need to know about lightning deaths and staying safe during storms:

How many people are stuck by lightning each year?

At 13 lightning fatalities, 2022 has already seen more deaths from lightning than all of 2021, which had 11 total lightning fatalities, according to the National Weather Service.

But 2021's number was a record low, Treadway said, and the number of fatalities in 2022 so far lines up with those of previous years.

"We're kind of right around where we expect to be," he said, adding that June through August typically is "the most active period for both lightning and for fatalities" amid summertime thunderstorms.

Looking back about two decades, Treadway said, there were typically about 25 to 40 deaths each year – a number that has "drastically decreased."

"Through education, we're really seeing that progress in the reduction of fatalities," he said.

PREVIOUS REPORTS: 3 dead, 1 injured in lightning strike near White House

When to seek shelter

Treadway said the National Weather Service uses the phrase "when thunder roars, go indoors" to help people remember when to seek shelter from lightning strikes.

He said people should seek shelter when they hear thunder even when it's not raining, because lightning can strike as far as 10 to 12 miles away from a parent thunderstorm. That means if you're close enough to a storm to hear thunder, you're close enough to be struck by lightning.

"You could be having a nice, sunny barbecue with a storm nearby," Treadway said. "But if you are close enough to hear the thunder, that's when it's time to take action."

For people who are deaf or hard of hearing, the weather service has another slogan: "See a flash, dash inside."

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What to do when you hear thunder

If you hear thunder, Treadway said, you should run inside a substantial building or hard-topped metal vehicle as quickly as possible. Picnic shelters and porches are not good enough protection, he said.

People should stay inside a safe building or vehicle for at least 30 minutes after they last hear thunder, Treadway said.

Sometimes, victims are struck inside buildings while using electrical equipment, Treadway said, adding that these deaths have been reduced with the advent of cordless phones and cellphones. Still, he said, people should avoid windows, electrical devices and plumbing, including sinks, baths and faucets, that put you in direct contact with electricity.

Treadway also warned people not to lie on concrete floors or lean against concrete walls because they can expand, chip away or explode if struck by lightning.

Never shelter under trees

Last week, strangers huddled together under a tree near the White House when lightning struck, The Washington Post reported.

The tragedy was unusual because a single lightning strike rarely kills more than two people, John Jensenius, lightning safety specialist for the National Lightning Safety Council, said in an email to reporters.

And he said the most recent multiple lightning fatalities have one thing in common: trees.

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Sheltering under a tree can be dangerous because "lightning tends to strike the tallest object in the immediate area, which is often a tree, Jensenius said. When lightning strikes a tree, the electric charge spreads outward in what's called a ground current.

"That makes the entire area around a tree dangerous, and anyone standing under or near a tree is vulnerable to this potentially deadly ground current," he said.

What if you can't find shelter?

If you can't find shelter, Treadway said, you should avoid isolated tall trees, towers or utility poles, as well as open areas.

"Don't be the tallest object in the area," he said.

People should also avoid elevated areas such as hills and mountain ridges and metal conductors such as wires or fences that lightning can travel along, according to the National Weather Service. People also should avoid lying flat on the ground, never use cliffs or rocky overhangs as shelter and stay away from ponds, lakes and other bodies of water.

If you're in a group, Treadway suggested, you should spread out "to reduce the risk of a lot of injuries or fatalities at once."

What to do when someone is struck by lightning

Cardiac arrest is often the immediate cause of death in a lightning strike, Treadway said. Act immediately by calling 911 and administering CPR. An automatic external defibrillator, if available, can also be lifesaving.

Contact News Now Reporter Christine Fernando at cfernando@usatoday.com or follow her on Twitter at @christinetfern.

This article originally appeared on USA TODAY: White House lightning strike: What you need to know to stay safe