Keep a safe distance from lightning and other tips for hiking safety
GOES Health Team
Hikes can turn dangerous if sudden storms hit and your crew of hikers need to keep a safe distance from lightning. If you are in areas of high elevation, the combination of losing cell service and a sudden storm can leave you with no way to research what the safest course of action is. Should you keep hiking until you get to a close camp? Descend away from the storm until it passes? If you find yourself in that scenario, having the GOES Health app will guide you in the moment.
Let’s go through the basics for storm safety — like keeping a safe distance from a potential lightning strike.
Lightning and thunder: What is it and why is it dangerous
Having a basic understanding of what lightning and thunder are can help you make sense of how lightning behaves.
Lightning strikes when static electricity builds up in storm clouds and an electric current flows between the ground and the storm cloud. This electrical release results in a 270,000 mph, 30-million-volt bolt of lightning.
The speed and energy in this bolt of lightning emits incredible amounts of heat (up to 50,000ºF). This immense amount of instantaneous heat supercharges the air molecules around the strike. The rapid expansion and cooling of these molecules create the rippling sound wave of thunder that you can hear up to ten miles away.
Since light travels quicker than sound, you’ll usually see lightning first, then hear its associated thunder.
Use the 30-30 Rule to understand if you are a safe distance from lightning
The “30-30 Rule” is a shorthand way to estimate how close you are to a potential lightning strike. When you see a flash of lightning, start counting the seconds until you hear thunder. Every five seconds of silence is equivalent to one mile between you and that lightning strike. 30 seconds between seeing lightning and hearing thunder means the strike is around six miles away from you.
If you hear thunder before 30 seconds has passed that means you should seek immediate shelter and stay there for the next 30 minutes.
If lightning strikes, find the safest shelter nearby
Not all shelters are created equal. These are some of the safer places you could take shelter in during a lightning storm:
- Indoors: Find sealed structures that will insulate and protect you from the elements.
- Parked and closed cars: Similar protection to being indoors. (However, convertibles or golf carts that are not closed leave you vulnerable to lightning.)
- Thick forest or deep valley: Thick forest canopies serve as a buffer and dissipate the energy from the blast point. Deep valleys are physically farther away from the storm clouds; the charge in the storm will be attracted to higher points that are closer to the charged particles.
- Deep cave: Make sure the cave is deeper than it is tall. Avoid a cave that is tall and shallow, as an electrical charge can travel over the ground, rock, or mouth of the cave and jump to you.
If none of these options are available, you can look at general lightning safety concepts to follow.
Three things to keep in mind when finding a safe shelter
If you find yourself outdoors without access to shelter during a thunderstorm, keep these three tips in mind:
- Go low
Get to lower elevation. Lightning is attracted to the tallest points at the highest elevations. If there is nowhere to go and it is unsafe to descend, look out for deep caves, ditches, divots or any other low points. Distance yourself from tall, isolated objects as they are the most likely targets for the impending strike.
- Avoid effective conductors
If you find yourself within striking distance of a storm, avoid conductors such as water and metal. Beware of the poles in your tent as they likely contain metal, making your tent a potentially unsafe option when seeking shelter.
- Lightning crouch
If you’re in an open and exposed area, distance yourself from all other objects and crouch low on the balls of your feet with your head down. The smaller you can make yourself in an open space, the better. If you’re with a group of people, it’s best for each person to stay at least 20 feet apart from one another.
A visual of a person performing the lightning crouch
What to do if you are struck by lightning
Getting struck by lightning is a severe injury, but the injuries vary dramatically. Only about 10% of lightning strikes are fatal. A lightning strike can cause severe nerve, muscular, bone and organ damage, not to mention short circuiting the heart and brain. While the heart will usually restart shortly after the strike, it takes longer for your brain to return to function. If a person is not breathing, it may be necessary to perform CPR. And just because a person seems fine, it doesn’t mean they are fine. Anyone struck by lightning should be taken to a medical professional immediately.
The GOES app has step-by-step guides for what to do, on the ready, should you ever be in this situation. Even without cell service, the GOES app has readily available information to keep you safe in the event of a sudden lightning storm
