Why does thunder make noise?

Why does thunder make noise?

Professor Gizmo (Amazing Science Presentations) gives expert video advice on: Why does thunder make noise?; Is it true that all snowflakes are different?; What makes rainbows? and more...

Well, when you have lightning you have thunder. The lightning is actually what causes the thunder. The lightning is this giant release of built up electricity in the sky and when that charge is released, it superheats the air and causes the air to expand, and that expansion just rushes through the whole area and carries that sound wave with it, and our ears pick it up as a big, loud, thundering crash.