Many people wonder about the safety of being in a car during a thunderstorm. While common beliefs vary, understanding the science behind how a car interacts with a lightning strike can provide clarity. Cars offer protection due to the Faraday cage effect, but a strike can still damage the vehicle. Knowing key safety measures is important.
Understanding Car Protection
A car offers protection from lightning due to the Faraday cage effect. This scientific principle means an electrical charge remains on the exterior of a conductive enclosure, preventing the electrical field from affecting the space within. The metal body and roof of a hard-topped vehicle form this conductive shell, directing the immense electrical current of a lightning strike around the occupants and into the ground.
It is a common misconception that a car’s rubber tires provide insulation from lightning. Rubber tires offer no significant protection against the immense voltage of a lightning strike. The lightning current is instead channeled through the metal frame of the car and then typically passes through the tires’ steel belts to the ground.
What Occurs During a Car Strike
When lightning strikes a car, the electrical current travels along the vehicle’s outer metal shell. While occupants remain largely safe due to the Faraday cage effect, the car itself can sustain considerable damage. Common damage includes harm to the antenna, electrical system, rear windshield, and tires.
The intense heat generated by a lightning strike can melt the antenna, cause sparks, and damage or destroy electronic components, potentially rendering the vehicle inoperable. Lightning can also shatter rear windows due to its interaction with defrosting wires and frequently destroys one or more tires as the charge passes through them to the ground. In some instances, a lightning strike might even ignite a fire within the vehicle.
Safety Measures During a Storm
While a hard-topped metal vehicle provides a safe haven during a lightning storm, certain precautions maximize protection. Remain inside the vehicle with windows closed. Avoid touching any metal components within the car, such as door handles, the steering wheel, or radio dials, as these can conduct electricity if the car is struck.
If driving during a thunderstorm, pull over to a safe location and turn off the engine and hazard lights. Wait at least 30 minutes after the last sound of thunder before leaving the vehicle or resuming travel. Vehicles that lack a complete metal enclosure, such as convertibles with soft tops, motorcycles, or fiberglass-bodied cars, offer less or no protection from lightning and should be avoided during a storm.