1.21 Gigawatts!": The Real Facts About Lightning

Lightning strikes a mountain peak
© Ryan Armstrong

The Facts

On July 19, 2003, Rick and Lisa Goff were enjoying an idyllic afternoon of fishing with their three children. They set up base near the shore of Crystal Lake, in the Uinta Mountains. As an early afternoon storm gathered overhead, the Goffs moved their lawn chairs under a tree for shelter. A bolt of lightning struck the tree and killed both parents instantly. The nine year-old boy and his two sisters, ages five and eighteen months, were airlifted to a hospital in Salt Lake City, where they eventually recovered from their injuries.

For the past forty years, the NOAA has listed lightning as the second largest source of weather-related deaths in the United States. In terms of mortality, it is exceeded only by flash floods. Local news agencies seem to report at least one lightning-related death in the Uinta Mountains each year—sometimes more. In Utah alone, lightning has claimed the lives of sixty people in the last fifty years. At any given moment, there are about 1,800 thunderstorms in progress around the globe. Worldwide, lightning hits the ground about 100 times per second.

In order to avoid becoming the victim of a lightning related injury, it helps to have a better picture of how lightning works. First, let’s look at the anatomy of a strike. In a thunderstorm, ice and dust particles are circulated through the atmosphere by high-speed winds. The turbulent air currents within the cloud cause collisions between the particles. These collisions generate static electricity. As electrical charge builds up on the dust and ice within a cloud, the positively charged particles gather towards the top, and negatively charged particles move to the bottom.

As a result of the building negative charge in the bottom of the cloud, a pool of positively charged particles gathers in the earth below. The positive charges in the ground concentrate in taller objects such as trees, telephone poles, and hills: wherever they are closest to the cloud. The difference in charge between the cloud and the ground continues to increase, until a lightning channel forms between the two. As electricity is transferred through the channel, the surrounding air is quickly heated to 50,000 degrees Fahrenheit. Rapid heating and cooling cause the air to expand, then contract. This produces a shockwave, which is then heard as thunder.

Lightning strikes the Utah desert
© Jeremiah Barber
Rocky outcroppings, hilltops, trees, bushes in the desert, and boats on water all make ideal targets for lightning. Long fences, bridges, and wet rope can also attract lightning strikes.

Since electricity looks for the shortest or easiest path between two points, lightning usually strikes at high points or at good conductors of electricity. Rocky outcroppings, hilltops, trees, bushes in the desert, and boats on water all make ideal targets. Long conductors like fences, bridges, and wet rope can also attract lightning strikes.

Unfortunately, lightning doesn’t always follow a consistent pattern. It has been documented to strike the ground up to 30 miles away from a storm cloud. Such bolts, referred to as positive lightning, are usually several times more powerful than ordinary lightning. The NOAA reports that more than 50 percent of lightning strikes occur after a storm has passed. The most simple and safe rule is this: If you can hear thunder, find a safe place to wait.

Avoid Being a Target

First and foremost, be aware of weather patterns and any associated risks in the area where you’ll be hiking, fishing, or camping. Take a few minutes to check the weather before leaving, and plan accordingly. For example, scattered afternoon thunderstorms are a common event in the Uinta Mountains of northeastern Utah. If you’re planning on crossing exposed ridgelines or bagging any peaks, keep a wary eye on the surrounding skies. Watching a thunderstorm in the backcountry can be an amazing experience, but safety should always be the first priority. If you can hear thunder or see lightning, get to safe ground immediately.

So if you’re in the backcountry, how do you find somewhere safe to wait out a storm? Sometimes the vast proliferation of lightning advice can seem confusing. However, if you consider how lightning and electricity work, all the rules can be boiled down to few simple concepts.

Most importantly, stay away from high points or anything that will act as a conductor. Tall or isolated trees, water, telephone poles, or metal structures can all attract strikes. Avoid open areas, where you serve as the tallest object around. An example of good cover during an electrical storm would be thick tree cover of uniform height. If there are no trees nearby, or only isolated trees, your best bet is to find a depression or other low-point where you can crouch in “lightning position.” Lightning position involves crouching with your feet planted squarely on the ground, with your head lower than your shoulders. If you have a sleeping pad or other insulator to place under your feet, it can help protect you from ground current.

Do not stand in the entrance of a cave, or under an exposed rock ledge. If the earth above you is struck, the electricity may arc through you in order to reach the ground beneath.

In light of the tragic story of the Goff family, there’s one more thing to consider. If you’re traveling in a group when a thunderstorm hits, spread out as you take cover. Thirty to fifty feet between group members should ensure that someone will be available to administer CPR and First Aid in the event of a strike.

Dealing with Lightning Injuries

Lightning injuries can usually be classified as occurring due to one of five mechanisms. A direct strike is exactly as it sounds. Of the five mechanisms of injury, a direct strike is the most likely to result in death. Individuals most at risk are those who remain out in the open during an electrical storm. The second mechanism of injury is direct contact. Injuries result when a person is touching another object that is struck, such as a tree. The individual acts as an alternate conductive route for the lightning, and shares some of the resulting electrical current. Side flash occurs when lightning hits a nearby object, then flashes through the air and strikes an individual as well. Again, the individual acts as an alternate conductive path for the lightning, but in this case direct contact is not required. Ground current is another potential cause of injury. When lightning strikes, the resulting electrical current dissipates into the ground, like rings of water in a pond. A person laying on the ground, or standing with legs spread, may be injured as some of the electrical current enters one part of their body and exits another. Unlike the other mechanisms of injury resulting from a lightning strike, the last does not result from electrical current. The blast of the shockwave, or thunder, resulting from a strike may knock people forcefully to the ground.

The individuals in these photos were either killed or injured by lightning only moments after their pictures were taken.
Photos courtesy of the National Weather Service.

In the event of a strike, it’s important to be prepared for significant injuries of almost any type. Lightning strikes are famous for unpredictable results. A few common results of lightning strikes are cardiac and respiratory arrest, burns, neurological disorders, and blast injuries.

Cardiac arrest results when the electrical current of the lightning disrupt the heart’s natural pacemaker. Often the heart restarts on its own, but in some cases it does not. If you see someone struck by lightning, it’s absolutely imperative to check their heartbeat and breathing immediately. CPR has a phenomenal success rate among lightning victims. In other cases of cardiac or respiratory failure, CPR usually has a success rate of 10% or less. In cases of lightning injury, CPR can have success rates of up to 90%. As such, normal rules of triage do not apply. If you find someone without a pulse or respirations after a lightning strike, begin CPR immediately.

Lightning burns usually aren’t too bad. Superficial burns are common, and they usually create feathery or fern-like patterns across the skin. Sometimes, however, the burns may be quite serious. Whatever the situation, lightning burns should be treated the same way as any other burn.

Neurological problems resulting immediately from a strike include temporary paralysis, blindness, deafness, nausea and vomiting, and seizures. While lightning strikes result in only a 10 percent mortality rate, over 70 percent of victims must deal with long-term neurological problems.

Injuries resulting from the blast can assume almost any form. If the victim is knocked to the ground, head or spine trauma is a possibility. Fractures, dislocations, lacerations, and puncture wounds may also occur based on the circumstances and terrain.

However you look at it, lightning is a potent force that should be taken seriously. Having to take shelter from a storm during an outdoor activity can seem like quite an inconvenience. Don’t be afraid to be the person who speaks up. Arming yourself with knowledge and taking the lead could make the difference between life and death.