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.

Monday morning brought the coldest temperatures Central Park has had so far this year. And temperatures haven’t bottomed out yet – not even close. An extra punch of arctic air pushes into the tri-state Monday night,

Preparations are underway as an arctic blast dives into the nation's interior and southern regions and pushes a snowstorm into the Mid-Atlantic and Northeast that will be followed by lethal cold.