Though it is theoretically possible to hear thunder and then see lightning, lightning actually causes thunder, so it has to come first. Thunder is the noise that's caused by the sound of the rapid expansion of air that gets suddenly heated by a bolt of lightning.
Lightning is extremely hot, and it can reach temperatures as high as 54,000 degrees Fahrenheit. When lightning hits the air, there's a huge temperature difference, and the air around the lightning bolt heats up very quickly as a result. The heat causes the air to essentially explode because it expands so quickly, which causes the loud cracking noise that starts a roll of thunder. The rumbling noise that follows the crack is a result of vibrations in the air column.
The speed of light travels much faster than the speed of sound, so people should see lightning before they see thunder. If someone hears a clap of thunder before they see a flash of lightning, the thunder they are hearing is the result of a different bolt that the person didn't notice. Because lightning occurs before thunder, lightning that is followed directly by the sound of thunder is a good indicator that a storm is quite close.Learn More
Although thunder and lightning occur at the same time, the lightning is seen before the thunder is heard because light travels at a much faster speed than sound. Sound waves can also bounce off molecules in the air, causing it to travel in different directions. This accounts for the distorted rumbling sound of distant thunder while thunder that is close by can be heard as a loud crack or booming sound.Full Answer >
In its simplest form, thunder is the result of a shockwave that breaks the sound barrier. Thunder forms as the air around a bolt of lightning becomes superheated and explodes, producing a shockwave. This shockwave travels faster than the speed of sound, which produces a sonic boom, just as a fighter jet does when it travels faster than the speed of sound.Full Answer >
Thunder is caused by lightning, so it cannot happen independently. The loud cracking sound of thunder occurs when lightning raises the surrounding air temperature by thousands of degrees, causing it to rapidly expand and compress, according to SciJinks.Full Answer >
Thunder is the sound created when lightning passes through the air, causing it to rapidly heat and cool, resulting in a massive pressure wave that can be heard. A single lightning bolt can raise the temperature of the air around it as high as 50,000 degrees Fahrenheit.Full Answer >