heavy snow and ice over the Martin Luther King Jr. holiday weekend.The setup involves an arctic high-pressure system pushing a cold front through the South and East over the next few days, ushering in another blast of frigid temperatures in the wake of the front.Moisture will be fed into the southern and eastern periphery of the cold air mass, and where temperatures are below freezing, there is an increasing threat of heavy snow and/or ice from the Southeast to the mid-Atlantic states into Friday.(FOX Weather) ((FOX Weather))Another piece of the puzzle includes the potential for a coastal low to develop along the cold front, which would enhance the threat of heavy snow for the mid-Atlantic and Northeast on Saturday.However, uncertainty remains high with respect to this potential coastal storm.