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Driving in Patagonia in the Winter
I was in the area a couple of weeks ago and there was no real snow. Infact most of the ski resorts where still closed. They do get storms in the higher altitudes. 4x4 is nice in the mountains anywhere in patagonia. Passes between Chile and Argentina do close, so be prepared. When getting stamps, ask for the 1 week or 30 days, even if you are only planning on being there for a day or two. If you get stranded, or something takes longer you will have some wiggle room..