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When folks go camping, whether into the wilderness or just locally, they have to be prepared to deal with whatever weather happens to be going on during their campout. If you've done any camping at all, chances are you've experienced a few thunderstorms, up close and personal in a tent, or while hiking and otherwise enjoying the outdoors.
It's my "day job" to be involved in hazardous weather, mostly from thunderstorms. Thunderstorms have a beneficial side, but on some occasions, they become more than a minor inconvenience for campers and those involved in outdoor activities. Through my Scouting experiences, I've had many opportunities to see how young people and their adult leaders operate during a campout.
Teenage boys are legendary for trying to act "macho" and getting stuck in situations that have become dangerous. Unfortunately, adult leaders sometimes can be just as silly and ignorant as the boys. It's often said "What you don't know can't hurt you." Absolutely wrong!! Ignorance and macho trips can result in terrible tragedies once in a while, and I doubt that anyone would want that on their conscience.
Since mountain thunderstorms tend to form in the early to mid-afternoon, it's generally advised that you do your hiking to the high peaks starting in the early morning, so that you can be on the way down from the peaks when the threat from thunderstorms is at its highest. However, the weather doesn't always behave normally. You need to keep your eyes on the sky and be prepared to abandon your hiking plans if a thunderstorm develops unexpectedly. You should be able to recognize developing thunderstorms before they begin to produce lightning. Fair weather clouds on a mountain may be puffy, but they are short and show little or no vertical development. When they begin to tower up and build into deep clouds with dark bases:
they are in the process of becoming thunderstorms. Sometimes, all that they do is to tower up but, generally, when this towering process begins, they go on to become thunderstorms. A cloud that is tall and beginning to flatten out at the top is definitely a thunderstorm:
If you see clouds like this around, and there are dark cloud bases overhead, then you are in a potentially dangerous place!
The first lightning flashes will coincide roughly with the time that rain begins; in the mountains, a lot of that rain might evaporate before it reaches the ground. Whether it reaches the surface or not, precipitating thunderstorms are a threat to produce lightning! During mountain thunderstorms, the peaks can be struck frequently and are no place for any wise hiker/camper to be.
Although lightning is seemingly random, there are some things you can do to minimize your risks if you are caught in the open during a thunderstorm:
Avoid being the tallest object around ... get as low as you can, but don't lie prone on the ground. Go into a squat, instead. If you're wearing a backpack, get it off and seek the best shelter you can find ... the idea is not that the backpack attracts lightning, but rather to facilitate getting to shelter quickly. Obviously, standing on a mountaintop is asking for major-league trouble!
It also is unwise to be near the tallest object around, like an isolated tree. Sheltering from the rain under a tree is often a factor in people being struck. Depressions in the rock, or shallow caves don't offer much protection from lightning on a mountaintop. Your best protection is to get down from the peaks as quickly as possible. Leave your gear behind ... whatever it contains is not worth your life! You can always go back and retrieve it after the storm passes.
There is no "warning sign" that will tell you reliably that lightning is about to strike; don't depend on having your hair stand on end, or whatever. The first sign of a CG may be the flash itself. Of course, if your hair does stand on end, then you should take steps to protect yourself immediately! If no suitable shelter is available, see points #1 and #2, above.
The time from the flash to the thunder is a rough measure of how distant the lightning is. If you see a flash and count the seconds, five seconds corresponds to about a mile. However, there is no distance from a thunderstorm that is absolutely safe! If you can see the lightning, then you are under some threat. CGs can occasionally jump out of a thunderstorm and strike the ground miles away, seemingly "out of the blue." What is currently being advocated is the "30-30" rule: take shelter if the time from seeing a flash to the time you hear thunder is 30 seconds or less, and don't resume activities until 30 minutes have elapsed from the last lightning and thunder.
[Image ©1976 A. Moller, used by permission]
You do not have to be directly hit by the lightning to be affected. Lightning can travel along the ground from a nearby strike to you. It can also jump from nearby objects that are struck.
Avoid being near fence lines and power lines that lead into areas where lightning is occurring. A flash can travel along the wires and jump to you.
Go/Call for medical help immediately if someone is struck! In the meantime, administer CPR to any lightning strike victims if their heart has stopped and they have stopped breathing. If they are simply not conscious, treat for shock (not electrical shock!). Dr. Mary Ann Cooper notes that there often is danger of hypothermia for victims, especially if they've been in the rain, and also says:
"[I]f there is no response to the CPR after 20-30 minutes, the chances of resuscitation and recovery are minimal. By then, the rescuers are also starting to tire. I think rescuers who are often emotionally attached to the individual need to know that they are not the ones that were at fault if they cannot resuscitate someone. They shouldn't feel they have to keep up CPR for hours, get exhausted mentally, emotionally, and physically which may potentially put themselves in jeopardy."
Hiking on the trail during a thunderstorm is not a wise thing to do if you are exposed. If you're in a forest, there are many trees about and your chances of being hit by a CG are not very high ... but along an exposed trail, you need to abandon your backpack and get as low as possible, again short of lying prone on the ground (see #1, above). Regrettably, shallow caves and overhanging rocks provide only shelter from the rain ... they do not increase your lightning safety by very much in otherwise exposed mountain locations.
During a thunderstorm, it is likely that campers will want to stay in their tents. This may provide shelter from the rain, but if you lie down in the tent, you are at risk from ground currents, which might well prefer to run through you from head to foot (or the other way around) as you lie in contact with the ground. Such a current flow would probably stop your heart. If you are standing up, but with your feet spread apart, a potential (voltage) difference could exist between your feet, encouraging current to run up one leg and down the other. It might not stop your heart, but it probably would be very unpleasant, given what it would be likely to pass through on its way! Hence, when sheltering from the rain in tents, you need to be taking steps to reduce the danger from ground currents. I don't know to what extent air mattresses and foam pads protect you while lying down through insulating your contact points with the ground ... I suspect that they will not make much of a difference!
The usual rules apply if you have chosen a campsite in an exposed location, where your tents are the highest objects nearby. If you have chosen your campsite unwisely in terms of lightning safety and a thunderstorm threatens, immediately abandon such a campsite and all your gear, and move to a better location for lightning protection. Campsites in among many trees are probably all right, in the sense that the chances of your particular location being struck are pretty low. However, you could still be unlucky, and the risk from ground currents and secondary strikes from lightning hitting nearby trees remains. If there is no better shelter (e.g., a motor vehicle) nearby than your tent, you will probably be lucky enough not to be struck, but there is no doubt that a substantial risk is associated with riding out a thunderstorm in a tent. Note that non-metallic tent frames don't mean much of a difference from metal frames, either, in terms of the threat. The same goes for various forms of "insulation" between the tent and the ground ... if a lightning flash has passed through thousands of feet of air (a terrific insulator), a few cm of rubber or whatever isn't going to make any difference that matters.
Being inside a vehicle places you inside a metallic "cage", and the current of a lightning strike tends to go through that frame rather than through you (the so-called "Faraday Cage" effect). It is not the rubber tires that protect you!
If someone in your group is struck by lightning, their heart and breathing may stop but they still have a chance to survive. Perform CPR on them until professional medical help arrives (see above). Make sure the medical team knows that they were struck by lightning, not by electric current from household power ... the treatment for lightning is not the same as someone that has been electrocuted by alternating current household power: for standard electrical shock, the medical team would administer fluids, which is the wrong thing to do with lightning victims.
Lightning hazards
Thunderstorms all produce lightning in varying amounts ... sometimes there's just an odd flash or two ... other times, the storms produce lightning nearly continuously, with lots of flashes to ground. It's the flashes from the cloud to the ground (CG flashes, for short) that create problems. They typically are only a small percentage of the total flashes produced by a thunderstorm; most lightning stays within the clouds. But it only takes one CG flash to get you! The human body is basically a bag of salty water, which conducts electricity a lot better than air, so the lightning will often try to travel through you to reach the ground.
Lightning and thunder are so common as to seem just part of the background. Often, as children, lightning and thunder frighten us. As young people mature (especially boys), it becomes a "macho" thing to show they are not afraid of a thunderstorm. Well, I'm certainly not advocating that we over-react, and head for home at the first sign of any thunderstorm ... but I want to suggest that we not go to the opposite extreme and pay virtually no attention to the threat that lightning strikes pose. Any thunderstorm should be a matter of concern, and the campers should already know what to do if the situation becomes hazardous.
It's pretty unlikely that you'll ever be struck by lightning. Scientists cannot make accurate predictions of when and where lightning will strike or how often, so for all practical purposes, it looks pretty random. Nevertheless, more people are killed by lightning year in and year out than by any other weather phenomenon; typically on the order of 100 people or so annually in the United States. Furthermore, lightning does not have to kill you to create major problems in your life. Several hundred people are affected by lightning in the U.S. every year, short of being killed. To get some idea of the non-fatal hazards of lightning from a medical point of view, check out this site and/or this one. Being struck is no joke and can affect you adversely for the rest of your life.
Anytime you're outdoors, you've increased your risk of being struck by lightning. For example, some golfers are struck every year ... many of you may have heard the story of Lee Trevino's non-fatal encounter! Another category of those who are at relatively high risk includes those who climb mountains. Since a lot of wilderness adventure camping includes hiking and camping at high elevations, campers and hikers are considerably at risk, whether they realize it or not. Consider the following statement from the 1997 Philmont Scout Ranch "Guidebook to Adventure":
by
Chuck Doswell
Senior Research Scientist, Cooperative Institute for Mesoscale Meteorology
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