[citation][nom]nebun[/nom]but can't you make your own cloud? isn't that what cloud seeding is?[/citation]
No. We have the internet now, so if you don't know what "cloud seeding" is, you can start with a simple google search. In case you're lazy, the idea behind seeding clouds is to provide supercooled water droplets with condensation nuclei. The technique used for cloud seeding varies on location and altitude, but often silver iodide or dry ice are used as they have structures that are conducive to the formation of ice. Supercooled water is at a temperature below the water's usual freezing temperature at STP, but stays in the liquid state due to the rapid motion in the air, which prevents ice crystals from forming. Thus, by providing a "nucleus" upon which supercooled water can build crystals, they will grow until they are too heavy to be supported by updrafts in the clouds. The crystals then fall as precipitation - rain in warm areas and snow in cooler areas.