A similar shift in the behavior of the jet stream has also contributed to the California drought and severe polar vortex winters in the Northeast over the past two years. An amplified jet-stream pattern has produced an unusual doldrum off the West Coast that’s persisted for most of the past 18 months. Daniel Swain, a Stanford University meteorologist, has called it the “Ridiculously Resilient Ridge” – weather patterns just aren’t supposed to last this long.
http://www.rollingstone.com/politics/news/the-point-of-no-return-climate-change-nightmares-are-already-here–20150805?page=4