Climate Central: For a political candidate, being labeled a "flip-flopper' can be a career killer. Just ask Secretary of State John Kerry, who lost his 2004 presidential race in part because of his reputation for voting against bills before he voted for them. Increasingly, though, the label also applies to North American weather, which has been lurching from one extreme to the next in a pattern that is consistent with global warming.
Climate studies have warned us to expect more frequent and intense extreme events,...