It really depends of what the beer is, how cold it gets, how long it stays cold, and how well insulated it is. Beer has a has a lower freezing point than water, as alcohol stabilises the liquid phase (if it didn't, then alcohol wouldn't be soluble in water). For a typical 4.6% ABV beer like your Nog this would drop the freezing point to around -2'C, while for my 6.5% Youngs AIPA would freeze closer to -3'C. Of course if your beer is boxed up like mine is, then it won't drop down as low as the outside temperature, but instead fluctuate around the average, never reaching the lowest or highest point during the daily temperature cycle. If I were you, I'd put a thermometer amongst your bottles and check it in the morning, and keep an eye on the forecast. If it looks likely that they might get close to -2'C, it might be worth bringing them in or putting a heater in there. If you haven't put them out yet, chucking a blanket over them will insulate them, reduce their temperature fluctuations, and delay the speed at which they head towards the average, but of course if they are already near freezing point, this won't be as an effective strategy. I keep mine in the unheated and uninsulated pantry, where the heat generated by the fridge and washing machines keeps it a good couple of degrees warmer than outside. I still store my higher ABV beers closer to the external wall though, just in case.