When dark clouds gather and lightning flashes across the sky, the first instinct of most people is to seek shelter. But with common advice warning us to avoid metal objects, many wonder: Is it actually safe to stay inside a car when lightning strikes?

How Lightning Works

Thunderstorms form when clouds become electrically charged — the upper parts carrying a positive charge and the lower parts a negative one. The difference in electrical potential between the clouds and the ground can reach hundreds of millions of volts. When the charge becomes strong enough, it breaks through the air’s resistance, creating a massive electrical discharge — lightning.

A single lightning bolt can carry up to 30,000 amperes of current and reach temperatures near 30,000°C, which is about five times hotter than the surface of the sun (National Weather Service, 2024). That’s powerful enough to destroy trees, fry electrical systems, or even be fatal to anyone struck directly.

Why a Car Can Be Safe: The “Faraday Cage” Effect

Contrary to popular belief, sitting in a car during a thunderstorm can actually be one of the safest options — if you handle it correctly. The reason lies in a physics principle called the Faraday cage effect.

When lightning hits a vehicle with a metal roof and frame, the electrical current travels around the exterior of the car and down to the ground, rather than through the cabin. This creates a protective barrier for anyone inside. The U.S. National Oceanic and Atmospheric Administration (NOAA) and Euro NCAP (European New Car Assessment Programme) both confirm that vehicles with enclosed metal bodies offer significant protect