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.

It's been a while since it last snowed in Mobile, but snow is in the forecast for the city on Tuesday, and a winter storm watch is in effect. The photo above is from the Mobile office of the National Weather Service from a rare south Alabama snow in December of 1996. Joe Maniscalco/National Weather Service

The good news/bad news is that bitterly cold air will move into the state overnight Sunday, dropping morning lows into the mid-teens for north Alabama and the upper teens as far south as Montgomery. Daytime highs may not get out of the 30s in central Alabama until Wednesday,