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Lightning: Information for Outdoor Recreation


The 30-30 Lightning Safety Rule

Lightning descending from the sky over a city

After you see lightning, if you cannot count to 30 before hearing thunder, go indoors. Suspend activities for at least 30 minutes after the last clap of thunder

If you are caught in a lightning storm while camping, climbing, or hiking, it is often difficult to find a protected place. However, you can avoid lightning injuries by taking certain precautions during outdoor recreation:

  • Check the forecast. Before hiking or climbing in the mountains, always check the weather forecast. Thunderstorms with lightning in the mountains occur most often during the summer months in the late afternoon or evening.
  • Follow the 30-30 rule. The beginning and the end of a storm are the most dangerous times. Even if you see blue sky, you may still be in danger. Be sure to follow the 30-30 rule for lightning safety.
  • Do not carry metal. Do not carry any metal objects (e.g., skis, ski-poles, antennas, ice-axes). Metal does not attract electricity, but it is a good conductor. Your chances of a direct hit are higher when you are carrying a conductor above shoulder level.
  • Avoid metal. Avoid metal objects. You are more likely to be burned if you are in contact with metal when you are struck by lightning.
A family hiking in the woods with backpacks

Did You Know?

The best place for shelter during a storm is inside a structure with four walls and a roof or an enclosed vehicle. Small, open shelters and tents do not provide protection. Large caves and valleys are protective. Small caves, overhangs, and wet stream beds are likely to be more dangerous than open areas because water conducts electricity and electricity can jump gaps between rocks.

Safety Tips

Remember these six safety tips when you are hiking or climbing during a storm.

  1. Separate from other members of the group to reduce the number of people injured by ground currents and side flashes between persons.
  2. Find refuge immediately, and do not continue to hike or climb for at least 30 minutes after a storm.
  3. Stay away from water and wet items (including fences and poles) because they can conduct electricity.
  4. If you are in the mountains, stay away from ridges, summits, single trees, power lines, and ski lifts.
  5. If you are in the forest, stay near lower trees.
  6. If you are caught in an open area, crouch down in a ball-like position (feet and knees together) with your head tucked and hands over your ears so that you are down low with minimal contact with the ground. Do NOT lie down. Lightning causes electric currents along the top of the ground that can be deadly over 100 feet away. Crouching down is the best combination of being low and touching the ground as little as possible.

IMPORTANT REMINDER: You can lessen your odds of being struck by lightning by following these precautions and safety tips while camping, hiking, or climbing.

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