actually it's provable that the weather is partly controlled, at least in Germany. http://www.br.de/themen/wissen/wetter-meteorologie-rosenheim... No need to be a conspiracy-theorist, it's simply true. They use that to avoid hail damaging the crops.

They clearly can manipulate the weather, the question is to what degree and when do they do it and with what aim: http://en.wikipedia.org/wiki/Weather_modification