Another disadvantage of touring in the winter is the lack of daylight hours. If you are camping, that means 16 hours or so in your tent during the winter. The biggest enemy however is getting wet. Rather it be from your own sweat or slush on the road, getting wet when it's cold is not good, if you are camping and you get wet in winter, it will be really hard to dry off. The sun is also lower making visibility just that much harder. Then throw in snow blindness.