I have a Lhasa Apso American Eskimo Mix. He's 1 year old and it's gonna be winter soon and ...?

I walk him 2-3 times a day for about 10min each and play with him in the backyard for 30min everyday. I only had him for 3 months and I'm wondering how cold does it have to be to NOT bring him out? There's booties and sweaters I can buy him but I prefer not smothering him in outfits if it's unnecessary because I heard that Lhasa's can stay out in the cold for a long time as well as American Eskimos. How cold can they stay out without any clothing?