NOAA National Weather Service Weather Forecast Office

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• The action of rising and descending air within a thunderstorm separates positive and negative charges.  Water and ice particles also affect the distribution of the electrical charge.
• Lightning results from the buildup and discharge of electrical energy between positively and negatively charge areas.
• Each spark of lightning can reach over five miles in length, soar to temperatures of approximately 50,000 degrees Fahrenheit (hotter than the surface of the sun), and contain 100 million electrical volts.
• An average flash could illuminate a 100 watt light bulb for more than three months.
• The rapid heating and cooling of the air near the lightning channel causes a shock wave that results in thunder.
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• All thunderstorms produce lightning and are dangerous. Lightning kills more people each year than tornadoes.
• Lightning often strikes as far as 10 miles away from any rainfall. Many deaths from lightning occur ahead of the storm because people try and wait to the last minute before seeking shelter.
• You are in danger from lightning if you can hear thunder. If you can hear thunder, lightning is close enough that it could strike your location at any moment.
• Lightning injuries can lead to permanent disabilities or death. On average, 10% of strike victims die; 70% of survivors suffer serious long term effects.
• Look for dark cloud bases and increasing wind. Every flash of lightning is dangerous, even the first. Head to safety before that first flash. If you hear thunder, head to safety!
• Blue Skies and Lightning. Lightning can travel sideways for up to 10 miles. Even when the sky looks blue and clear, be cautious. If you hear thunder, take cover. At least 10% of lightning occurs without visible clouds overhead in the sky.

1. Postpone activities promptly. Don't wait for rain. Many people take shelter from the rain, but most people struck by lightning are not in the rain! Go quickly inside a completely enclosed building, not a carport, open garage or covered patio. If no enclosed building is convenient, get inside a hard-topped all-metal vehicle. A cave is a good option outside but move as far as possible from the cave entrance.
2. Be the lowest point. Lightning hits the tallest object. In the mountains if you are above tree line, you ARE the highest object around. Quickly get below tree line and get into a grove of small trees. Don't be the second tallest object during a lightning storm! Crouch down if you are in an exposed area.
3. Keep an eye on the sky. Look for darkening skies, flashes of lightning, or increasing wind, which may be signs of an approaching thunderstorm.
4. Listen for the sound of thunder. If you can hear thunder, go to a safe shelter immediately.
5. If you see or hear a thunderstorm coming or your hair stands on end, immediately suspend your game or practice and instruct everyone to go inside a sturdy building or car. Sturdy buildings are the safest place to be. Avoid sheds, picnic shelters, baseball dugouts, and bleachers. If no sturdy building is nearby, a hard-top vehicle with windows closed will offer some protection. The steel frame of the vehicle provides some protection if you are not touching metal.
6. Listen to NOAA Weather Radio. Coaches and other leaders should listen for a tone-alert feature during practice sessions and games.
7. If you can't get to a shelter, stay away from trees. If there is no shelter, crouch in the open, keeping twice as far away from a tree as it is tall.
8. Avoid leaning against vehicles. Get off bicycles and motorcycles.
9. Get out of the water. It's a great conductor of electricity. Stay off the beach and out of small boats or canoes. If caught in a boat, crouch down in the center of the boat away from metal hardware. Swimming, wading, snorkeling and scuba diving are NOT safe. Lightning can strike the water and travel some distance beneath and away from its point of contact. Don't stand in puddles of water, even if wearing rubber boots.
10. Avoid metal! Drop metal backpacks, stay away from clothes lines, fences, exposed sheds and electrically conductive elevated objects. Don't hold on to metal items such golf clubs, fishing rods, tennis rackets or tools. Large metal objects can conduct lightning. Small metal objects can cause burns.
11. Move away from a group of people. Stay several yards away from other people. Don't share a bleacher bench or huddle in a group.

1. Avoid contact with corded phones.
2. Avoid contact with electrical equipment or cords. If you plan to unplug any electronic equipment, do so well before the storm arrives.
3. Avoid contact with plumbing. Do not wash your hands, do not take a shower, do not wash dishes, and do not do laundry.
4. Stay away from windows and doors, and stay off porches.
5. Do not lie on concrete floors and do not lean against concrete walls.