To understand weather MANIPULATION you need to understand WHAT is being manipulated: The Hydrological cycle is the weather cycle. There are only a few places things can be changed… hope this helps:
http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hyd/smry.rxml
Here is a link queued up to show you how they EXTRACT moisture via “evapotranspiration” in New Mexico.. I show you a real example in about 7min
https://www.youtube.com/watch?v=YnZo1Obu_CY&t=596s