That’s a heck of a theory you got there, handy.
Yes, you can.
Report from the Montreal ice storm of '98:
We were without power for almost exactly one week (less a couple hours on the second day, but we had jumped ship by then). One saving grace was that the temperature didn’t go below the high 20s and was above freezing during that week. Since the average low in January is around 10 F and well below 0 is common enough, this really made a huge difference. But that temperature hovering around freezing was also the cause of the ice storm (which was actually three ice storms over a five day period). There are five major power lines that bring power from James Bay to Montreal, a distance on the order of 1000 miles and four of them came down. Had the fifth come down, there would have been no water and it would have been a major disaster. If 46 people died, I imagine not many from hypothermia. A couple, 93 and 94 years old who lived two blocks from me died from smoke inhalation after starting a fire. A neighbour (whom I know and from whom I learned the news) tried to get them to the local town hall where cots and a soup kitchen had been set up, but they refused.
But to get back to the effects of the storm, all I can say is we coped. I drained my radiators and water system. For two nights my wife and I slept at my downtown office. Then they turned all power off downtown and I found a friend who had power. Actually, we had gone there to take showers and my department chair called to tell me not to return. (One thing that spooked me personally was that our phone was also out, but that was just sporadic and repaired the second day, but we had bailed by then.) We then stayed with the friend for 4 days until our power was back.
So we spent one night here, sleeping with many blankets, then two nights in my office, then 4 with a friend. The friend actually had several families staying there and we had a great old time. The one thing that was frightening was when the water went off for about an hour and a half. There were also sporadic power cuts, but not for more than a couple hours at a time and they were clearly intentional.
Everyone had a story. My friend and I drove to one house (of another friend of his) to show them how to drain the water system if necessary. He had a fireplace and when we discovered that his hot water was heated with gas, we realized he had some source of heat. Turned out the guy’s wife knew it all along and had been showering regularly. They had a fireplace and were campling in front of it. My next door neighbour had a Franklin Stove and a good supply of wood and he and his wife were cooking and sleeping by it.
But to get back to the OP, when I took anthropology we read that native Australians used to sleep in the open with temperatures that got as low as 40 F at night. So I wonder about those Indians. Is it just that some people are cold adapted and others not? I just don’t know, but I am surprised that people would die at 40 deg. It is mighty unpleasant, yes, but I never thought it was fatal.
I remember moving into a new apartment on New Year’s Eve and having no heat but the stove. Chicago can get mighty cold at that time of year, and my son was only about a year old. We finally found the maintenance dude and he turned it on, but it was just awful.
With zero windchill you would be safe. Hell, your body heat in wrapped in a blanket would be more than enough to keep you warm.
One of my early highschool science teacher (or some movie in the class) stated that because air is a great insulator, if you kept still the warm air next to the skin would keep you fairly insulated without any air movement.
For myself, since I’m very warm bodied, I would probably be fine with just my regular clothing (this is from a guy who turns on the a/c in the winter, damn building I live in just turns on the heat up to 85!). My GF on the otherhand would probably die when the temp reached 60 
Hmm…
Anyway, water takes heat from your body ten times as fast as air does. Thus, in theory, if the room is 55 deg & you’re naked it would take say, in theory, 10 times 25 minutes= 250 minutes for a hypothermic reaction to start.
The body would try to keep your main central organs warm, thus take some blood from your brain & other areas & so your memory is probably gonna go as one of the first things. One might want to write a letter to oneself before that happens “Dear Myself, if you can’t remember who you are, your name or where you are, you’re too cold & you need to get warm ASAP” 
right.
And when you are then confused you will totally understand the note.
:rolleyes:
I lost power for 14 days in January of 1993 (the great Seattle area Inaugaration Day storm). The daytime temps rarely exceeded 40 degrees and everynight was below freezing. Thank God for the pile of firewood I had saved up and the generator I had fixed the day before the storm. The house stayed a livable temperature and we could watch TV too. The phone and cable never went out. We did spend 3 different nights in a local hotel for the pleasure of a hot shower and a warm bed. But with a small menagerie of animals at home, we couldn’t stay gone for long. Other than burning up a weeks worth of vacation, I survived the ordeal rather well.
Sometimes people forget that they can use a gas oven when there is no electricity to stay warm. Also the hot water heater should work & you can take a hot bath. Some modern appliances use electric starters but the hot water heater I bought a couple years back doesn’t use one of those.
My house is really old, so inside it is only ten deg warmer than outside. So, in theory if it was 45 outside & I was naked & didn’t have any blankets, hot water, oven, electricity, firewood, Etc (Highly improbable), I’d start getting a reaction around 250 minutes.
Carbon monoxide poisoning is a very real risk when doing that. It’ll do in an emergency, but it’s not recommended.
Besides the second poster in this thread already mentioned that days ago.