Lightning safety: when thunder roars, go indoors

Lightning strikes the United States roughly 25 million times a year, mostly in summer. It kills about 20 people in the U.S. each year and badly injures hundreds more. The main rule is simple: go inside as soon as you hear thunder.

When thunder roars, go indoors

If you can hear thunder, lightning is close enough to strike you. Lightning can hit more than 10 miles from a storm. Even if you see blue sky, you could still be in danger.

The NWS puts it plainly: there is “no safe place outside” when thunderstorms are nearby. Many lightning deaths and injuries happen because people wait too long to get to shelter.

What counts as safe shelter

Safe:

• A substantial building with electricity or plumbing, such as a home, office, or shopping center
• A fully enclosed, hard-topped metal vehicle with the windows rolled up

Not safe:

• Tents, picnic shelters, and dog houses
• Porches, gazebos, and dugouts
• Open vehicles like convertibles, motorcycles, and golf carts

Wait 30 minutes after the last thunder

Stay inside until at least 30 minutes have passed since the last thunder you heard. Each new rumble of thunder starts the 30 minutes over. Wait before going back to the pool, the field, or the yard.

Staying safe indoors

Lightning can reach you inside through wiring and plumbing. During the storm:

• Do not use corded phones. Cell phones and cordless phones are safe.
• Stay off computers, game systems, and other devices plugged into the wall.
• Avoid water: no baths, showers, or washing dishes.
• Stay away from windows and doors, and stay off porches.
• Do not lie on concrete floors or lean against concrete walls.
• Bring pets inside, and do not leave them chained to a tree.

Whole-house surge protectors can help protect appliances.

If you are caught outside

Nowhere outside is safe, so keep heading for shelter. Until you reach it:

• Get off hills, ridges, and peaks right away.
• Never lie flat on the ground.
• Never shelter under a lone tree or a rock overhang.
• Get out of and away from pools, ponds, lakes, and other water.
• Stay away from things that carry electricity, such as barbed wire fences, power lines, and windmills.
• If you are with a group, spread out.
• Do not carry metal objects like golf clubs, fishing poles, or umbrellas.

If you are on the water, head back to shore as soon as you see a storm coming.

If someone is struck

• Call 911 right away. It is safe to use a cell phone during the storm.
• It is safe to touch the person. People struck by lightning do not carry an electrical charge.
• Check whether they are breathing and have a pulse. If they are not breathing or have no pulse, start CPR or chest compressions, and keep going until help arrives.
• If they are breathing, check for burns and other injuries.

Plan around the forecast

Check the forecast before outdoor plans. If thunderstorms are expected, reschedule, or make sure safe shelter is close by. Older relatives who spend time outside, gardening or walking, can follow the same rule: if they hear thunder, they head inside.

Learn the difference between severe thunderstorm watches and warnings.