Even places with lots of water will give you trouble in the winter, the water is frozen. The ice can be feet thick in some areas, so water becomes another life threatening need. You can’t just walk around sucking on ice cubes all day to hydrate your self, you will lower your core temperature and die from hypothermia. Your only real option is to melt the snow or ice with an external heat source, wood fire in most cases. But you will need a vessel to hold the snow and ice, better get these in the bug out bag. A sheet of black plastic can be used to melt snow on sunny days and a container at the down hill end to collect the water.
Living outside is very different from going grocery shopping when it is cold outside. When you are running out to get some milk or pick the kids up from school and it is cold out. You can do it with your coat or sweater on. When you are out in it all night and all day, day after day, you need a new level of warm clothes. Your feet will get cold and once they are cold it is hard to get them warm again. So if you live in a cold area invest in some insulated foot wear, it might just save you. Your blue jeans are fine for running errands, but if you are going to be living outdoors you are going to want some good base layer, long johns. Layers of clothing are best, that way you can take a layer off, if it gets too warm and add a layer if it gets too cold.
The other areas you won’t think of until it is too late is your head, neck and hands. A good winter hat is a must, there are many types. But you want one that is soft and comfortable, and covers your ears and as much of your face as possible. A hoodie helps with keeping your neck warm in the cold wind, but a scarf works too. And finally to your hands, there are many types of gloves and they vary to your needs. Thickness and bulk are generally for cold, and thinner material is for less severe cold. But sometimes you need to use your fingers or thumbs. They make all different kinds so take a look around and see whet is out there to meet your needs. I like a mitten type of winter glove that also flips open to expose your fingers as needed. The same set of mittens also has a flip open thumb and are very good in extreme cold.
So don’t fool yourself into thinking that bug out bag is really going to save you until you take a long hard look at what it takes to live outside your home, in the cold real world of winter.