Evergreens do not need nearly as much light while temperatures are low so any spot on your porch should be OK.
This is important for you to hear Vesper.
A few days......heck, even a week without direct sun will not harm the tree and the warmth of the house has the potential to help a great deal while the temperature is extreme.
Wrap the pot in blankets and put it over against the wall of the house. I have two thermometers outside my back door. One is out away from the the house a bit and the other is right up against it. The one against the house is regularly 2Ã‚Â° - 4Ã‚Â° warmer.