"Last year was an exceptionally good year for not having fatalities. This year is starting out as an exceptionally bad year, compared to the past five years," said John Jensenius, the lightning expert for the National Weather Service. "It's been every day or almost every other day in June."
So far this month, he said, there have been 11 U.S. deaths. By comparison, there were eight fatalities in total last June and four through the 18th day of that month. In 2007, there were 12 deaths in the entire month of June and three by the 18th. The 30-year-average for June is 13 deaths, he said.
Lightning strikes more than 400 people each year in the United States,and about 60 of those lead to death, according to the National Weather Service. Most lightning strikes and fatalities occur during July.
Usually, he said, fatalities from lightning strikes increase toward the end of the June, as the school year ends and people spend more time outside.
"It's a combination of outdoor activities and lightning that results in people getting killed," he said. "Part of the increase can be attributed to bad luck, part of it to people taking too long to go indoors when storms approach."
The most recent fatality took place in Columbia, Mo., Wednesday.
According to the Boone County Fire Protection District, Georgette Tillett, 23, was walking across an open field after a fishing trip with two friends when she was struck by lightning. By the time firefighters arrived, she was unconscious and not breathing. An hour later, she was pronounced dead at a local hospital.
As the National Oceanic and Atmospheric Administration kicked off its annual Lightning Safety Awareness week Sunday, it urged people to exercise caution during the summer.
The organization's key advice is to go into a fully enclosed building or hardtop vehicle at the first clap of thunder and remain indoors for 30 minutes after the last clap of thunder.
In a number of cases, Jensenius of the National Weather Service said, people would have been saved if they had just moved indoors five to 10 minutes earlier.
Dr. Mary Ann Cooper, a lightning injury expert, said her advice is simple.
"When thunder roars, go indoors," she said, quoting the National Weather Service's motto. "No place outside is safe when thunderstorms are in the area."
Lightning can strike 10 to 15 miles from a thunderstorm, she said. So check the weather reports and make alternate, indoor plans if you know that a storm is on the way.
But while experts say your chances of being struck by lightning dramatically decrease once you're inside a building with both plumbing and wiring, they warn that hazards still exist around the house.
Once you're indoors, experts caution against contact with electrical equipment and plumbing. Here's a list of specific threats to avoid: