The latest edition of the Polar Vortex Blog has dropped and this week our experts explain how a major disruption of the polar vortex WAY up in the stratosphere can (but not always) impact the weather we feel at the surface. First it starts when a huge, planetary-scale wave in the atmosphere travels into the stratosphere -- which only occurs when the winds in the stratosphere are blowing west-to-east, as is generally the case during the northern hemispheric winter. It is complex, as there are a l