Reese Witherspoon had to deal with LA's temperamental Winter weather when she ran errands yesterday. She was spotted wearing a warm-weather-friendly black silk dress while shopping with a friend after putting on a heavy black parka while heading into a fitness class in Santa Monica. Despite what looked like a casual day, Reese has a busy week ahead of her. The trailer for Mud, Reese's new movie with Matthew McConaughey, was released earlier this week ahead of its premiere at Sundance. Reese and Matthew are both no strangers to the famed film festival, having attended the event multiple times. Check out the best celebrity Sundance moments before the festival kicks off this weekend.