Amid a dangerous arctic blast over much of the U.S. this week, snow and ice may bring major travel disruptions and power outages in the South, forecasters warned.

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.

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.