Hi Nathan, I live in Minnesota, and have often wondered about how they survive in the cold. I have found what I think are sasquatch tracks on approx. 7 occasions. Mostly in the spring/summer/fall seasons.
Once snowmobiling with a buddy, we went down a set of railroad tracks on our way home. The snow was 3 - 4 ft. deep, and still coming down. It was around midnight, and we came to a downed power line on the tracks, from the weight of the snow on it. We veered off the tracks into a small clearing in a willow swamp. My buddy took this time to tinker with his sleds carb, while I sat on mine and had a smoke.
I looked around, and saw a set of fresh tracks going across the clearing at an angle, and one of them was right next to my sled. I assumed it was made by a deer we had scared, judging by the distance between strides (about 6 ft.), I leaned over and shined my lighter in the track next to my snowmobile.
At the bottom, I was surprised to see a large human shaped track, including toe impressions. I had my buddy look at it, and his reply was it was a snowmobile boot print. His explanation of the toe impressions was the ribbing you find going down the toes of some boots. I knew that wasn't a good enough explanation, as the ribs wouldn't leave that big or pronounced impression.
Also it didn't account for the length between strides, with very little to no drag in the deep snow. We were in the middle of nowhere, at least 2 or 3 miles from any road, in the middle of a snow storm, at around midnight. We hadn't seen any other tracks on our whole trip down the railroad tracks, until we veered off into the swamp.
What was most interesting about the tracks, is they sank all the way to the bottom, and looked like they had generated enough heat to melt the snow at the bottom so you could see the grass at the bottom.
You could also see the ice forming around the edges, where it was re-freezing. These were fresh tracks, and due to the snow falling, would be filled in a matter of minutes.
Therefore I believe a sasquatch has a higher body temperature than humans, much like a dog or horse who don't seem to be bothered by winter temps., as long as they are acclimated to it gradually.