Most of the United States is being assailed with extreme winter weather this week as Arctic air blasts south from Canada, snow tracks up the Northeast coast and a potentially crippling winter storm takes aim at the South.

Residents across the country from the Northern Plains to the tip of Maine are bracing for dangerously low temperatures as residents along the East Coast contend with a thick blanket of snow — and more snowfall in the forecast.

The snow is likely to fall on Sunday from the Appalachians to New England. New York City may see its largest snowfall in years.

While it's not clear what impact a mix of rain, freezing rain, sleet and snow may have on the capital city, officials say now is the time to begin preparations.

An already active winter is about to shift into overdrive as a trio of storms over the weekend and into next week deliver snow to the Midwest, East and possibly as far south as the Gulf Coast.