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Seek appropriate shelter during threat of lightning

  • Published
  • By Eric T. Hoehn Safety Office
  • 88th Air Base Wing

WRIGHT-PATTERSON AIR FORCE BASE, Oh -- Summer is peak season for one of the nation’s deadliest weather phenomena: lightning. In the United States, lightning kills more than 40 people a year.

While no place is absolutely safe from lightning, some are much safer than others. The safest location during lightning activity is a large, enclosed building, not a picnic shelter or shed.

Examples of unsafe buildings include carports, covered but open garages, covered patios, picnic shelters, beach shacks or pavilions, golf shelters, camping or large outdoor tents, baseball dugouts and other small structures such as sheds and greenhouses that do not have electricity or plumbing, which provides a path to ground.

The second-safest location is an enclosed metal vehicle, car, truck or van, but not a convertible, bike, or other topless or soft-top vehicle. If you seek shelter in your vehicle, make sure all doors are closed and windows rolled up. Do not touch any metal surfaces.

If you’re driving when a thunderstorm starts, keep in mind that a lightning flash hitting the vehicle could startle you and cause temporary blindness, especially at night. A brief break from driving might be in order.

Seek safe shelter when you first hear thunder, see lightning or dark, threatening clouds developing overhead. Count the seconds between the times you see lightning and hear the thunder. You should already be in a safe location if that time is less than 30 seconds. Stay inside until 30 minutes after you last hear thunder.

Your first and only truly safe choice is to get to a safe building or vehicle. If you cannot get to shelter, consider the following tips. While they will not entirely prevent you from being hit, these strategies can decrease the likelihood:

  • 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.
  • Stay away from tall, isolated objects. Lightning typically strikes the tallest object — that may be you in an open field, clearing or on the water).
  • If there is a high chance of thunderstorms in the forecast, curtail your outdoor activities.

To estimate the distance between you and a lightning flash, use the “flash-to-bang” method: If you observe lightning, count the number of seconds until you hear thunder. Divide the number of seconds by five to get the distance in miles.

If thunder is heard, lightning is:

  • 5 seconds after a flash, 1 mile away
  • 10 seconds after a flash, 2 miles away
  • 15 seconds after a flash, 3 miles away
  • 20 seconds after a flash, 4 miles away
  • 25 seconds after a flash, 5 miles away
  • 30 seconds after a flash, 6 miles away

Get to a safe location if the time between the lightning flash and rumble of thunder is 30 seconds or less.

Make the most of your time outdoors and enjoy beautiful Ohio — but not when lightning is present.