Five young lives have been ended by lightning in less than a week, a deadly reminder of one of summer's leading hazards.

"Typically, July marks the peak in lightning activity. It's also the time when people are vacationing, so they are outside and they are vulnerable to lightning," said John Jensenius, a lightning safety expert at the National Weather Service.

But why so many young people in a few days? "I don't have an answer for that," Jensenius said, "It's all very sad."

Landon Dillard, 16, of Macon, Georgia, was riding a bicycle at a summer camp in Colorado when he was struck down on July 3.

Two days later, 19-year-old Korey Moore of Swansea, South Caroling, was riding a personal watercraft when hit. The next day lightning claimed Stephanie Dawn Kirpes, 23, of Woodbridge, Virginia, while she was jogging along the shore in Virginia Beach, Va.

And on July 7, two 16-year-olds were killed by lightning: Ben Richter on his family farm at Watertown, Wisconsin, and Lucian Ellis of Sampson County, North Carolina, who was in a beach hut sheltering from a storm.

"In terms of safety, the most important thing for people to know is if the sky looks threatening or they hear thunder, they need to get inside a substantial building - one with wiring and plumbing - or a hard-topped metal vehicle immediately," said Jensenius.

According to the Weather Service, a safe building has a roof, walls and floor, such as a home, school, office building or a shopping center. They provide safety because lightning will usually travel through the wiring or the plumbing into the ground. That means stay away from showers, sinks, hot tubs and electronic equipment such as TVs, radios and computers.

Picnic shelters, carports, dugouts, sheds and other partially open or small structures are not safe, the agency says.

Finding a safe place is often easier said than done, of course, but Jensenius stresses caution, pointing out that lightning can reach miles from the cloud where it originates. Known as bolts from the blue, these strikes are not common but they have caused deaths.

For campers and others outdoors far from a car or shelter, lightning experts warn people to stay away from tall objects like trees. Lightning tends to hit the highest thing around. And by the way, in an open field, that may be you.

The United States rang up 45 lightening deaths last year and there have been 16 so far this year.

The National Weather Service's advice for folks threatened by lightning when there is no safe building or automobile available:

- Do not seek shelter under tall isolated trees. The tree may help you stay dry but will significantly increase your risk of being struck by lightning.

- Do not seek shelter under partially enclosed buildings.

- Stay away from tall, isolated objects.

- Know the weather patterns of the area. For example, in mountainous areas, thunderstorms typically develop in the early afternoon, so plan to hike early in the day and be down the mountain by noon.

- Know the weather forecast. If there is a high chance of thunderstorms, curtail your outdoor activities.

- Do not place your campsite in an open field on the top of a hill or on a ridge top. Keep your site away from tall isolated trees or other tall objects. If you are in a forest, stay near a lower stand of trees. If you are camping in an open area, set up camp in a valley, ravine, or other low area. A tent offers no protection from lighting.

- Wet ropes can make excellent conductors. If you are mountain climbing and see lightning and can do so safely, remove unnecessary ropes extended or attached to you. If a rope is extended across a mountain face and lightning makes contact with it, the electrical current will likely travel along the rope, especially if it is wet.

- Stay away from metal objects, such as fences, poles and backpacks. Metal is an excellent conductor. The current from a lightning flash will easily travel for long distances.