When temperatures drop or snow starts to fall, many of us hibernate inside under warm blankets — after stocking up on bread and milk, of course. But not our dogs.

Cold? They love the cold! They run around the yard with heads held high and tails streaming, bucking like frisky foals.

But it's even more amazing when it snows. That baffling, stupendous, chilling white stuff is for catching, rolling around and racing in. Like this:

What is it about the cold and snow that makes our canine friends so absolutely bonkers?

"I think it's just fun. It's something new. Plus snow is like a brand new toy," says certified dog trainer and behaviorist Susie Aga of Atlanta Dog Trainer. "They have fur coats on, and they're warm all the time so they feel good when it's cold."

Dogs have fun in the snow for probably the same reason little kids have fun in the snow: It changes their usual playground.

"It's really no different than us humans (particularly children), who find many different forms of entertainment in the winter," says certified professional dog trainer Katelyn Schutz in Wisconsin Pet Care.

"We toss snowballs, build snow forts, and hurdle ourselves down snowy hills on sleds, skis, and snowboards. It's no wonder our dogs follow our lead!"

This newness isn't just what they see, of course, but it's what they smell and what they feel when they're outside romping in the snow.

That's why this owner helped his senior dog experience all the fun of a snow day.

"More than anything, I suspect that the very sensation of snow on the body is engaging for dogs," Alexandra Horowitz, PhD, author of "Inside of a Dog: What Dogs, See, Smell, and Know," tells Scientific American.

"Have you ever run through the shallow waves of the sea? Why does kicking up sand and seawater make us happy? I can't say. But it is clear that it does."

Not all dogs love the snow and cold, Aga points out. Hairless breeds shiver and get too cold when exposed to frigid temperatures. (Above all, just pay attention; your dog will let you know if he's not enjoying the weather.) They might need doggie sweaters or jackets before heading outside to play.

But cold-weather breeds like Siberian huskies, Newfoundlands and great Pyrenees have dense coats and were bred to withstand winter's wallop.

"For snow dogs, that's when they come alive," Aga says. "They become more energetic. It allows them to run and play without getting overheated. They just feel freer in it."

When your dog is racing and bounding around in the snow yelling, "Wheeeee!" it's obvious he's having fun.

"Dogs will play with something that is interesting and moves in a different way — it feels interesting," Dr. Peter Borchelt, a certified applied animal behaviorist, told the Dodo.

"It's about novelty and creating different movements — they're trying to learn what is this thing and what to do with it."

Plus, snow is really fun to catch.

Editor's note: This story has been updated with new information since it was published in December 2019.

Mary Jo DiLonardo covers a wide range of topics focused on nature, health, science and anything that helps make the world a better place.

Why dogs love the cold and playing in the snow
You might hibernate when it snows, but your dog loves playing in a winter wonderland.