Consider it a late-arriving visitor from the North Pole, or a hurricane without the palm trees. The polar vortex chilling much of the country – including Western New York – is a large-scale “cyclonic circulation” generated when cold air from the frozen Arctic comes into contact with relatively warmer bodies of water, unfrozen patches of ocean.

The National Snow and Ice Data Center, based in Boulder, Colo., describes this effect, also called a “polar low,” as “small, intense cyclones that form over open ocean during the cold season ... Polar lows range in size from around 62 to 310 miles in diameter. Wind speeds average around 50 miles per hour, although they can occasionally reach hurricane strength (64 miles per hour).”

The vortices are an Arctic constant, especially in winter, making news only when they stray beyond their regular stomping grounds, like Siberia.

The sort of good news is, while the vortices develop much faster than the typical tropical hurricane, according to the snow and ice center, “they dissipate just as quickly, lasting on average only one or two days.”

Meteorologist have not yet reported what caused this particular North Pole phenomenon. The last time our area felt it in a big way was in the 1990s, when the polar winds dipped farther south than usual in six different winters.