Is ‘Winter Reactivity’ a Thing? How Cold Weather Can Change Your Dog

As the days get colder and shorter, you might be noticing yourself feeling a little... different. Maybe you’re more gloomy, lazy, or sleepy than you were in the height of summer when you were hitting your step goals ever day. You might find yourself napping or snacking more often than usual (no shame!).

This is kind of par for the course for humans during hibernation season, but you might not realize that your dog is going through the same thing. The colder weather and darker days impacts their mood and behavior significantly, resulting in something known as “winter reactivity.” 

In other words, your dog’s behavior may change during the colder months. Lorraine Rhoads, an environmental biologist and the director of health and safety at Dogtopia, says that many dogs experience increased sensitivity, excitability, or agitation in winter. This is caused by reduced daylight, colder temperatures, changes in routine, and decreased outdoor activity.

“These environmental shifts affect both physical comfort and emotional regulation, which can lead to more reactive behavior on walks or at home,” Rhoads says.

The winter can influence a dog’s mood in several ways. “Reduced daylight affects circadian rhythms and hormone regulation, including melatonin and serotonin levels, which can shift energy and emotional balance,” she says. In the winter, many of us reduce our dog’s outdoor time because we are understandably fed up with going outside in the cold ourselves. This means that they get less exercise, and this can lead to frustration, restlessness, and decreased stimulation.

This actually happens a lot.

Sian Lawley-Rudd is a dog trainer and the founder of Lavender Garden Animal Services. She says that winter reactivity is more common than people think, and while not a clinical term, it describes a pattern she sees every year. Around this time, her clients become more on edge, more vocal, or more easily triggered. The lack of time outdoors and increased disruption to their routines can affect a dog’s emotional state.

“Some dogs get more frustrated or restless because walks are shorter or less enriching,” says Lawley-Rudd, adding that our emotions play into it, too. If we’re rushing through a walk, our dogs can feel that tension. Rhoads agrees, reminding us that dogs are highly attuned to our feelings: “If a human in the household is suffering from the winter blues, the dog may pick up on and mirror those lower energy and mood states.” As difficult as it can be, it’s worth trying to slow down and enjoy your walks together.

Even if you are careful to make sure that your dog gets as much stimulation and outdoor exercise in the winter as they do the rest of the year, there are other changes that affect their mood and behavior. Sensory changes — such as strong wind, icy surfaces, and altered scents — can make some dogs feel more cautious, while others may become more excitable, Rhoads says.

In fact, dogs have a heightened sense of smell in colder weather. Moisture and temperature affects the strength of smells, and when the temperature drops, scent molecules become more dense. This means scents are heavy and close to the ground, making it easier for dogs to sense them.

It isn’t all about the temperature, either. Even in climates that are relatively warm, the reduced daylight still impacts your dog’s mood, affecting their circadian rhythms, hormone regulation, melatonin and serotonin levels. This can shift energy and emotional balance in dogs, just like it can for you.

All of these factors can worsen several behaviors. Leash reactivity, for example, can increase because dogs have excess energy and may be startled by winter-specific stimuli, such as bundled-up people or fast-moving objects appearing suddenly, Rhoads says.

“Barking, pulling, and jumping can intensify when dogs are not able to release energy consistently. Territorial or attention-seeking behavior may escalate when dogs spend more time indoors,” she adds. She says it isn’t only about what happens outside, either. Indoor behavior can also worsen. “Your dog may even redirect pent-up energy and the need for mental stimulation into household items, furniture, or inappropriate digging. Some dogs even regress with house training if they are reluctant to go outside in the cold.”

You can help them stay calm and safe in the winter.

You can’t avoid the winter every year, but there are measures you can take to make the changes easier on your dog and you. Rhoads says that a consistent routine is the most effective way to support them during the colder months.

“Short-but-frequent outdoor trips help prevent pent-up energy, and structured exercise such as purposeful walks, training breaks, or controlled play keeps dogs mentally and physically balanced,” she says. “Many dogs benefit from adding daycare to their routine as well because it functions like an indoor dog park where they can socialize, play safely, and accumulate miles of step activity even on the coldest days.”

You can also try to create positive associations with winter conditions by offering rewards for calm behavior outside. Sometimes, of course, you just have to stay inside. Depending on where you live, the conditions may become dangerous or extreme, particularly for certain breeds of dog. When that happens, you can turn to indoor enrichment. Mental-stimulation tools, like puzzle feeders, foraging games, snuffle mats, and trick-training sessions can keep your dog entertained.

Rhoads also suggests hallway fetch, indoor agility setups or controlled tug sessions to ensure they get enough exercise and burn energy. Lawley-Rudd also suggests indoor “sniffaris,” where you bring in scents from the outside world. Scattering pine cones, leaves, and other fun-smelling items indoors can help your dog to enjoy the outdoors without actually going outside (as long as you’re OK with a few leaves in your house).

Above all, says Lawley-Rudd, it’s not about giving your dog more adrenaline, but offering them outlets that help them to decompress and soothe their nervous system. Most importantly, that means predictable routines and gentle enrichment. Winter is a time to slow down, and by meeting your dog where they are, you can approach this tricky season in a way that supports both of you.