GEORGIA (WJBF) – Thursday is the fourth day of severe weather preparedness week for the state of Georgia.

Meteorologist Jenna Petracci explains how lightning forms and safety tips.

Lightning is one of the leading causes of weather fatalities in the United States. And it can strike when you least expect it.

Lightning is caused by the buildup and release of electrical energy between positive and negative charges from Earth and a thunderstorm. It can strike miles away from the actual storm, which is known as a Bolt from the Blue.

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So it may not even be raining where you are, but it’s important to stay inside when a storm is in in your region. When we hear thunder, that means lightning is nearby. You can calculate how far away you are from lightning by counting the number of seconds between the lightning and thunder and dividing by 5. For example, 15 seconds between lightning and thunder would mean it’s 3 miles away.

You definitely don’t want to be out on the water during a storm, since electrical currents travel easily through water and metal. Also remember that lighting tends to strike the tallest object in an open space, so you don’t want to be out in a field. Enclosed vehicles are generally safe, but the best place to be is inside a building.

Next time you hear thunder roar, be sure to head indoors!