I wouldn't want to spend a long time up there, just a few days.

I have felt wind chills thar are -40 to -50 below. It's not the same as actual temperature, but it can be dangerous. If the temp is +10 with lots of wind, you can get frostbite faster than if it's -10 with no wind. When the windchill is -40, the wind literally stings your face. It's not an extreme pain or anything, it's tolerable. But only for a few minutes, longer than that you get frostbite.