Lightning is one of nature’s most extreme phenomena. When that flash rips through the sky, it’s heating the air it passes through to an astonishing temperature - around 30,000°C. That’s roughly five times hotter than the visible surface of the Sun, which sits at a “cool” 5,500°C.
The heat doesn’t last long - a bolt of lightning is over in a few millionths of a second. But during that fraction of a moment, the air it touches explodes outward as superheated plasma. That violent expansion is what creates the sound we hear next: thunder. Thunder isn’t the sound of the bolt itself, it’s the sound of air being shoved aside by lightning’s heat.
Lightning travels at about 270,000 miles per hour, but light is roughly a million times faster. That’s why you always see the flash before you hear the boom. Count the seconds between them and divide by five - that’s roughly how many miles away the strike was.
