Of course there is a link between appetite and cold weather. The unit "calorie" is used for the amount of energy needed to HEAT 1 gr of water by 1 kelvin. You can be sure that you need more energy to keep your body warm in winter. My coach said to increase the food intake by 10% in cold weather. But we do not ride in SUCH cold weather. Maybe when it's -5 or 0, but more than that...I use the trainer
Your body is telling you that it needs more energy, don't neglect its signals