Experts have warned that Friday's freezing temperatures were simply a warm-up and that this weekend will bring a big chill for 140 million people - almost half the nation - that could prove fatal for the unprepared - and will continue through the winter. With the Northeast still reeling from the huge storm that dumped as much as two-feet of snow across the region and was responsible for the deaths of 16 people, a new weather system is threatening to bring record low temperatures to the Midwest as a polar vortex barrels over the United States. 'It's the mother lode...