What causes the sound of thunder? | Scientific Explanation?

Thunder is the loud sound you hear when lightning happens nearby.

When lightning strikes, it heats up the air around it very quickly, like turning on a super-hot stove in an instant. This hot air expands, or gets bigger, really fast, which pushes the air around it and makes a big wave of sound, just like when you blow into a balloon and it makes a whoosh.

This wave of sound travels through the air until it reaches your ears. The farther away you are from the lightning, the more time it takes for the sound to reach you, so thunder can feel like it’s coming from all around you or even rolling in, just like a big, loud echo.

Sometimes, if there are clouds above you, they can bounce the sound back down, making it seem like thunder is getting louder or repeating, kind of like when you shout into a tunnel and your voice comes back to you again!