The North Pole has unleashed "a large pool of Arctic air" that’s headed straight to the U.S., setting the stage for "record cold temperatures and dangerously cold wind chills," warns the National Weather Service in a new report.

The term “polar vortex” usually refers to the gigantic circular upper air weather pattern in the Arctic region. It is a normal pattern that is stronger in the winter and keeps some of the coldest weather bottled up near the North Pole.

A lobe of the polar vortex, a ring of freezing air typically found near the North Pole, will once again move into the central and eastern states this week, bringing some of the coldest air of the winter season so far — and even helping fuel yet another winter storm in coming days.