I've not heard of a polar vortex before-what is it and does it ever affect the northwest?
The Polar Vortex is a genuine phenomenon, though the term has been considerably over-used. Ever since Weather disaster films have become popular (Sharknado is one of the worst...or best...examples)...it seems some meteorologists have jumped on the bandwagon. The polar vortex is a circulation pattern that is located near the poles, and tends to keep the coldest air 'bottled up' near the poles. Occasionally, the vortex splits and part of it slides south, carrying very cold air with it. It is not a pattern that directly causes snow in the Puget Sound area.