A cross-country storm, a blast of Arctic air and an outbreak of showers and thunderstorms are threatening to snarl traffic and pile up delays at airports through the Thanksgiving holiday weekend, one of the nation's busiest travel periods.

Mother Nature is about to serve up some unappetizing conditions for the millions of Thanksgiving travelers: sloppy weather, snow, the coldest temperatures since February and a potentially disruptive storm are on the way through the holiday weekend. Here’s a day-by-day look at what to expect this week.