When it rains are the clouds closer to the ground?

Answer 1

Actually, yes they do tend to be lower. Clouds which are full of water and ready to rain are heavier and therefore float at a lower altitude. This is clearly demonstrated in the Pacific Northwest region of America, where clouds routinely dump large quantities of rain on the western slopes of the Cascade mountains before gaining enough altitude to go over the mountains.

Answer 2

A cloud that starts to rain does not get any lower than similar clouds that are not producing rain. Some of the rain, however evaporates and increases the humidity of the air below the cloud. Often fractostratus or scud cloud will develop below the cloud that is producing the rain and it looks as though the clouds are lowering.