I will be moving across country and have several leather bags that will be left in the car overnight. What temperature is too cold for them? I would hate for them to be ruined because they froze. Thanks!!!!!!
We have lived in the colder parts of Canada and I have never babied my leather items including my vintage coach, D&B, Chanel and Hermes. The leather will stiffen while it is frozen so stuff the bags to hold their shape. Make sure they are well padded on the outside too so they don't dent each other.
When you unpack them let them come up to room temperature and the leather softens again.
Museums routinely freeze new textile and leather acquisitions as a chemical-free method to destroy pests so your bags should be fine for a night or so. Just make sure they are packed in a way they will not get misshapen.