According to the National Weather Service, a polar vortex will impact most of the country this weekend, here is what you need to know.

A blast of Arctic air is set to cover much of the United States with temperatures below freezing starting on Friday and into next week, impacting millions of Americans in nearly all of the contiguous states.

A polar vortex dipping down from Siberia will bring a cold front with frigid temperatures to nearly 300 million Americans. See maps of the arctic blast.