How much does a cloud weigh ?

A lot. If 1lt = 1 kg of water. Depends on the size. But I'd say it's pretty heavy.

1.1 million pounds for cumulous clouds

almost as much as your mom

Enough to rain on your parade.

I know this won't clear up the cloudy question, but clouds like people come in all weights and sizes.

couple of tons to hundred to few thousand tons, depending on their size and density.

well its wireless...get it...wireless sounds like weightless...get it...get it

It depends if it's been raining or not.

That's rather personal! :)

How much water does it contain?

Nothing, else they'd fall...