eli5: How do (presumably very heavy) clouds stay suspended in the sky? More specifically how are they floating AND flat on the bottom?

Question

And what causes them to suddenly drop all of that water in the form of rain.

Judging by the amount of rain they must weigh a ton.

In: 337

Answer 1

So clouds are actually the visible tops of much larger mountains of moisture. The line on the bottom is where the air gets too cool to hold it all in a gaseous state – so everything above that is visible.