The cold temperatures are coming from a not uncommon expansion in the Polar Vortex, which are counter-clockwise rotating air currents that typically hang over the Arctic.

Abnormal weather events and severe winter storms could be caused by a disrupted polar vortex. Find out here how the polar vortex affects the weather.

A polar vortex dipping down from Siberia is bringing a cold front with frigid temperatures to millions Americans. See maps of the arctic blast.

Some areas of the U.S. may see temperatures as low as -20 or -30 degrees early next week as arctic air from Siberia rolls in.

Snow and winds are likely to disrupt traffic, trigger flight cancellations, and cause headaches for people traveling to D.C. for Inauguration Day. Baby, it’s cold outside, and it’s about to get even colder for much of the United States.

However, a deep freeze, thanks to the polar vortex dipping down from Siberia, is about to bring even harsher arctic blast to nearly 300 million Americans starting this weekend. Maps show where and when the cold front will arrive.

Here's a detailed forecast and timeline of when NYC will see snow on Sunday, how many inches to expect and what's forecast to happen when a polar vortex sweeps the area next week: WARNING: This story contains details of intimate partner violence and may affect those who have experienced it or know someone who has.