Xinhua: America’s jet stream is heading north and getting weaker, which may mean less rain in the drought-stricken South and Southwest and more storms in the North, new research reveals. The northern jet stream "is the dominant thing that creates weather systems for the United States," said study co-author Ken Caldeira, a climate scientist at the Carnegie Institution of Washington in Stanford, California. "Basically look south of where you are and that’s probably a good guess …