The answer depends primarily on the climate and weather where you'll be training during the winter. If temperatures regularly drop below freezing, you may want a shoe that has added insulation. Similarly, if you think you'll have to run on snowy, icy, slushy, or frequently wet surfaces, a winter running shoe with built-in waterproofing and extra grip (via deeper lugs or built-in ice spikes) is a good idea. If these types of conditions only occur occasionally, you might be able to get through winter with your standard summer shoes.