Lightning is a scary thing. It’s blindingly bright, and the sharp crack of deafening thunder closely follows its passage. If lightning strikes you or lands nearby, it can severely injure you or do worse. Unless you’re inside a sturdy shelter, you don’t want lightning coming anywhere near you.
So what will happen if lightning strikes your car while you’re in it? Are you safe in a car during a lightning storm? Is there anything you can do to stay safe?
The answer depends on some of your vehicle’s traits. Is its body made of metal? Does it have a hardtop, an open top, or is it a convertible? Are all the windows closed or open?
Generally, a car with a metal hardtop and body will protect its occupants from a lightning strike. The metal outer shell shields the people inside the vehicle.
That assurance goes out the window if the vehicle is a convertible. Convertibles provide little protection for their occupants if a lightning bolt hits them. It doesn’t matter if they deploy their roof–a cloth top offers no protection from lightning strikes. And while some convertibles use a metal hardtop, they probably won’t give the same level of protection as vehicles with roofs integrated into their frames.
A similar issue affects vehicles with fiberglass bodies. Since their outer shell uses a nonmetallic material, they can’t produce the Faraday cage that protects the occupants of a metal-bodied car from lightning strikes.
Other vehicles that don’t protect their operators and passengers from lightning include bicycles, motorcycles, and outdoor recreational vehicles (RVs) with open-shelled bodies.
Have you heard of Faraday cages? Also called Faraday shields, they’re enclosures that block electromagnetic fields from entering or leaving them. They consist of a continuous covering or mesh made of conductive material.
When an electrical field outside the Faraday cage comes into contact with the enclosure, the electric charges within the conducting material redistribute themselves. The internal field cancels out the external field, preventing the latter from affecting the space within the enclosure.
So what does a Faraday cage have to do with your car protecting you from lightning? Vehicles with metal bodies act as a large Faraday shield, and lightning is a massive electrical discharge. Thus, your car can usually prevent lightning from reaching you.
Most ground-to-cloud lightning strike cases hit either your car’s antenna or the roofline. It just so happens that those parts are usually your vehicle’s highest points.
Upon striking your car, the lightning shoots through your vehicle’s outer metal shell. The electric surge keeps going downward into the wheels and tires, blocked from your car’s interior and occupants by the Faraday cage effect. Finally, the lightning bolt leaves the tires through the latter’s contact point with the road surface.
In many cases, you can continue to drive safely during a thunderstorm. However, the lightning storm might grow constant and severe enough to deter you from proceeding with your journey.
Except for emergencies that force you to hurry, stop your vehicle, and wait until the thunderstorm ends. Look for a sturdy shelter that won’t draw lightning strikes and covers as much of your car as possible.
Close the windows and keep them shut until the weather clears up. An open window disrupts the Faraday cage, potentially allowing the lightning to enter the interior.
Sit neatly and keep your hands to yourself. Avoid physical contact with anything made of metal or metallic material, especially near the outer shell. Electricity travels poorly through the air, so it will generally stick to the Faraday cage’s conductive material. However, the current passing through the outer shell might change course if it finds a path with lesser resistance than air, such as your hand and arm.
Similarly, keep your hands away from the gearshift and steering wheel. While these control features usually feature leather or rubber covers that insulate them, their internals use metal materials that conduct electricity.
Furthermore, the gearshift and steering wheel connect to other parts that touch the car’s outer shell. Some electricity coursing through the metal shell during the lightning strike might go up the steering column or transmission instead. You might get injured if the steering wheel or gearshift cover can’t provide enough insulation against the current.
Just because your car can protect you from lightning doesn’t mean it’s invulnerable to the strike. The typical lightning bolt delivers 300 million volts and about 30,000 amps. Even if almost all that power goes into the ground, some of the discharge might damage your car’s parts.
The parts that commonly get damaged by lightning strikes include the following:
Many cars have an antenna sticking out of the side of their roof. In older models, the antenna picks up radio transmissions. Nowadays, they detect other forms of wireless transmission, such as satellite communications.
A lightning strike can heat the car antenna until it partially melts or burns. The burning antenna might also explode, showering sparks and bits of molten metal.
The electrical system is another possible casualty of a lightning strike. While your car employs fuses or circuit breakers to protect against excessive voltage, the discharge might overwhelm that safety system. A lightning strike might overload parts and potentially cause electrical fires.
Depending on the damaged part and the severity of the issue, you might not be able to drive your car until you’ve fixed the problem.
Contrary to popular belief, tires can’t protect against lightning strikes. While rubber is an insulating material, and the air inside the hollow part also slows down electrical currents, lightning is too powerful.
Furthermore, many tires contain steel belts. These steel-belted tires offer superior flexibility, but the metal’s conductive nature allows lightning to travel through it. The overwhelming voltage can melt the tire, which can lead to accidents on the road if you’re driving during the lightning strike.
Does your vehicle have windshield defrosters that rely on heat grids? A heat grid is a network of thin wires that run across the rear windshield. When a current runs through the wires, the heat grid warms up, melting ice on the windshield glass and preventing condensation from forming.
Unfortunately, heat grids are highly vulnerable to lightning strikes. The grid might overheat and burn if the electric discharge passes through the wires. The overloaded heat grid might even shatter the windshield.
Even with these potential vulnerabilities, your car will protect you from a lightning strike. However, it’s crucial to take good care of it in return. If your vehicle gets struck by lightning, check its parts once you reach safety.
While unlikely, lightning can still strike your car under a thunderstorm. If it happens, follow the steps below:
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.