I personally don't believe in leaving animals outside all the time, but I understand that many people do. If you do leave your dog outside, please be sure to provide them with what they need to survive.
Providing a dog house
The breed of dog you have also makes a difference as to how much cold your dog can stand. When my Golden Retriever Jake was alive, he loved the cold and snow. He would lay down and roll around in the snow. Contrast that with my Olde English Bulldog, Jes, she can't get 'her business' completed quickly enough to come back in. The difference? Their coats. Jake had long, thick fur - and two coats of it. Yep, Golden Retrievers have two coats of fur. Conversely, Jes has short hair. Imagine how cold your head would be if you had a haircut like a marine and you'll understand why Jes needs more than her natural coat to keep her warm.
Jake always loved going for walks in the winter. But his paws would get dry and crack. I learned that was from the salt they used to melt the ice on the roads. That's horrible for a dogs paws. If your dog wants to go for walks during the winter, be sure you wash their paws when you come in. And, just like you wouldn't run your hands under hot water after exposing them to freezing temperatures, don't run your dog's paws under water that is too hot.
I bought Jake some booties
I know some people think that clothes for dogs are stupid. And I must admit, before I got Jes, I thought a sweater on a dog was just a fashion statement or silly women going overboard with their "purse dogs." Now I'm embarrassed by that thinking because having a short-haired dog for the first time I realize that, just like people, different size dogs need different things.
Educate yourself on what your breed needs and provide accordingly.