Just as school delays and closings are broadcast to protect children from inclement weather, you should be concerned for the outdoor safety of your pets. While most dogs and cats come equipped with fur coats, their coat does not ensure they have sufficient protection from the winter cold when temperatures dip below freezing. In general, cats should be kept indoors when temperatures near freezing to protect them from hypothermia and frostbite. Since dogs differ in their cold tolerance, there is no strict temperature cut-off for when it is no longer safe for dogs to be outside. Puppies and elderly dogs are less able to effectively regulate their body temperature than adult dogs, and this should be taken into consideration when deciding how long they can safely stay outdoors in both cold and warm weather. Dogs with some health conditions such as hypothyroid disease, anemia, and laryngeal paralysis (which is also exacerbated by warm weather) may be less tolerant of cold weather. Even a dog’s conformation or “body type” can play a role—dogs with short legs that are lower to the ground may be more susceptible to the cold if their abdomens get cold and wet from the snow.
The only published guideline for cold weather safety for dogs is the Tufts Animal Care and Condition (TACC) Weather Safety Scale. A more user-friendly cold weather safety chart (below) can give you an idea of the level of concern you should have for your dog based the temperature and conditions outside.
Gearing Up for Winter
As illustrated in the chart, one very important factor in determining how safe it is for your dog to be outside is the presence of wet weather (snow, sleet, rain). Dogs’ fur provides warmth but when the fur is wet or matted, it does not provide as effective insulation. Furthermore, if a dog’s fur gets soaked, the moisture can actually draw heat away from its body, making it even colder. Keeping a dog’s fur well-groomed and dry can increase its cold tolerance. While not included in the chart, wind chill also certainly plays a role. On very cold and windy days, wind draws heat more quickly from the outer surfaces of a dog’s body, decreasing the amount of time it can safely be outdoors.
A waterproof coat can provide an added layer of insulation, a wind barrier, and can repel moisture. Although it may seem silly to dress a dog in a coat, a waterproof coat with good coverage—from a dog’s neck to the base of its tail, and covering its abdomen—can greatly impact the temperatures a dog can safely tolerate. Dogs also lose heat through their footpads. Winter booties, if accepted by your dog, can provide additional warmth as well as protection from ice chunks and deicing chemicals that can cause irritation to dogs’ paws and can be toxic if ingested.
When pets are exposed to cold weather for too long, they can suffer from hypothermia or frostbite, which can be life threatening. The cold weather safety chart provides a guideline, but there is no substitute for common sense. If your dog starts to shiver, seems anxious or uncomfortable outside, or his or her extremities seem cold, bring your dog indoors and get him or her warm and dry as soon as possible.
A Side Note: Since cats are less tolerant of near freezing temperatures, it is safest for them to be strictly indoors during the colder parts of winter. Outdoor cats may seek warmth and shelter from the cold by settling under the hoods of cars or in the wheel wells, which can be deadly. If your vehicle is accessible to cats, before starting your car, bang on the car hood or honk the horn to startle any cats or wildlife and give them a chance to escape without injury.