“Food is critical this time of year because you have to feed that furnace,” says Nester. The calories you consume will be converted into much-needed body heat and can help stave off hypothermia. He recommends carrying 3,600-calorie S.O.S. Emergency Food Rations ($10; Amazon), which won’t freeze: “Even if it’s the middle of winter, you’re not going to break a tooth,” he says. “If you’re looking to have something in your vehicle and leave it there for a year or two, these don’t require cooking and can handle extremes of heat or cold, whether you’re in Phoenix or Minnesota. [They’re] basically like a shortbread cookie.” Nester himself also carries packets of freeze-dried camping food and instant soup in his vehicle.