Zombie mode

Zombie mode is a state characterized by a stark lack of awareness and autonomy upon waking, which often results in turning off alarms without fully waking up, and then going back to sleep and oversleeping (sometimes with no memory of ever waking up). This is more likely the more sleep deprived one is, and can be imagined as your body forcing you to get the sleep it thinks you need by preventing you from waking up. This most often occurs when waking from SWS, since this is the deepest sleep stage.

If you find that you're cold when getting up, having a warm robe or sweater (and perhaps even a thermos with a warm drink) next to your alarm can provide yourself with another option to warm up other than going back to bed.
See alarms for more help with minimizing your chances of zombie mode ruining your adaptation.