“A dog’s circulatory system is actually quite good in regards to dealing with the cold,” Dr. Goldstein told us, noting that the average dog is much better equipped to deal with winter chill than summer heat.

But not all dogs are created equal when it comes to staying warm.

Miniature dogs (like chihuahuas), poodles and poodle mixes have the hardest time because they have hair, which is “not anywhere near as protective or thick as fur,” Dr. Goldstein said. Wolfish northern breeds with long fur, like huskies and malamutes, do best. Labradors and golden retriever types are somewhere in the middle.

“When we get goose bumps, it doesn’t do much because we’re not as hairy as we once were,” Dr. Goldstein said. “But when a dog gets goose bumps, it makes their hair stand up, increasing the barrier they have between the outside and the skin, and that coat is good at minimizing the loss of heat.”

“It would be hard to imagine a larger dog that would need a jacket,” he added. “You’re doing it more for the owner and the cuteness than for the dog.”

If you do decide to get your pup a winter get-up, the key body parts to keep warm would be the face, mouth and nose, because that’s where their heat evaporates, according to Dr. Goldstein. But because covering a dog’s whole head is not exactly realistic, do your best to cloak their belly or abdomen.