Humans aren't the only ones who get cold in the winter, even under all that fur, our furry friends can get quite cold, resulting in many of the same problems humans can get from exposure to cold-including hypothermia.  There's several things you can do to help keep your pet cozy with the weather change.  

The first one that comes to mind is bundling up-especially for non-cold-weather-breeds, it might be worth your while to invest in a pet sweater or jacket for walks or going outside.  You might think they look silly, but there's some pretty nice ones out there, and if it'll keep your pet from freezing it might just be worth it.  An additional idea is to give your pet booties so that snow and ice doesn't build up on their paws.

Some things you can do inside the house are to make sure your pet is drinking plenty of water, and to make sure that their bed is warm and away from drafts.

These are just some of the things you can do to keep your pets warm and safe during the snowy season.  Look around for more advice, you can never be too careful in the cold.