The past is an indication of the future. Look at the Scablands in the NW. That was caused by an ice dam on one of those early lakes breaking. I don't know what is used now, but years ago silver iodide was used to seed clouds. The rain/snow nucleus would form around the particle. Having more particulates in the air would urge this along. Maybe this is why the 2 rain delays in the ALCS last night. Denver has ozone warnings with the altitude. Like you, I don't trust the ones trying to make a buck.