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Animal Behavior
How Hot Is Too Hot When Leaving Your Dog In the Car?
Essential facts to help avoid putting dogs at risk of heatstroke.
Updated July 11, 2023 Reviewed by Abigail Fagan
Key points
- Heatstroke is an avoidable cause of canine suffering.
- Dog guardians need to understand the safe temperature range for leaving dogs in cars.
- Dog guardians need to know how dogs cool themselves and how quickly cars heat up.
As loving dog guardians, we always want what's best for our furry companions. Whether running errands or planning a day out, the decision about whether to bring our dogs along if it means leaving them in the car for a period requires careful consideration. Before we head out, it is vital that we are in possession of the facts about dog physiology, how they cool themselves, how quickly cars heat up, even with the windows partially open, and how quickly a situation that seems safe to the uninformed, can become dangerous or even deadly.
To get the latest, I talked with Jon Sutz, who is passionate about preventing dogs from suffering from heatstroke when left in cars, and who created the educational website HeatKills.us.
Understanding the Risks
As Sutz notes, leaving dogs in hot cars can quickly turn into a life-threatening situation. Contrary to popular belief, it doesn't require extreme heat for a car's interior to become dangerous for dogs. Even at temperatures as low as 70 degrees Fahrenheit, dogs are at risk of heatstroke and serious health complications.
Heatstroke occurs when a dog's body temperature rises to dangerous levels, exceeding their ability to cool down effectively. Dogs are particularly susceptible to heatstroke because they rely on panting as their primary cooling mechanism.* Within just 10 minutes, dogs can begin to experience brain and organ damage when left unattended in a car, regardless of the external temperature. Older dogs, young puppies, and dogs with preexisting medical conditions can be particularly susceptible to overheating.
Exact statistics on the number of dogs who die each year from being left in hot cars are not readily available. Many cases of dogs dying in hot cars go unreported or are not captured by official statistics. Additionally, incidents may vary depending on geographic location, climate, public awareness, and reporting practices. However, it is well-documented that leaving dogs unattended in vehicles during hot weather can lead to heatstroke and even death and numerous incidents are reported each year. Sutz created a page containing some tragic stories from around the world. He warned me: “These stories are really tough to read, and some contain video and photos of the aftermath, and they can be triggering. They were, to me, compiling and editing them.”
Rapid Temperature Increase
To emphasize the urgency of the situation, it's helpful to understand how quickly the temperature inside a car can rise. As the HeatKills graphic to the left shows, even with the windows partially open, the interior of a car can experience a temperature increase of 19 degrees Fahrenheit within 10 minutes, and a staggering 29 degrees Fahrenheit within 20 minutes. This rapid rise in temperature can have severe consequences for our beloved companions.
To get a visceral sense of how quickly a car can heat up, Sutz recommends this YouTube video by renowned veterinarian Ernie Ward. Just watching it will make you sweat.
Expert Insights
As HeatKills.us notes, a slew of veterinary and animal protection organizations, such as the American Veterinary Medical Association (AVMA), the American Society for the Prevention of Cruelty to Animals (ASPCA), and local animal control agencies, consistently work to raise awareness about the dangers of leaving dogs in hot cars. They encourage dog owners to prioritize the safety and well-being of their pets by avoiding this potentially life-threatening situation. In other words, the safest choice you can make is often just to leave your dog at home.
The Safe Temperature Range for Dogs
While the risks associated with leaving dogs in cars are apparent, it's also important to understand the safe temperature range for our canine friends. An external temperature below 70 degrees Fahrenheit is generally given as the safe cutoff, but factors such as direct sunlight and humidity can also affect temperatures inside a car and can increase risks for a dog. A safer, more conservative cut-off, in my opinion, is 60 degrees. I personally don’t feel comfortable leaving my dog Bella in the car when the temperature climbs above 60 degrees. (I also don’t leave her in the car during the winter months when the temperature gets much below 50 degrees. Call me paranoid, but this is just what feels right to me.)
Preventive Measures
To ensure the well-being of our dogs, consider these preventive measures:
- Leave your dog at home: Much as you might enjoy our dog’s company, leaving your dog at home in a safe and comfortable environment is often the best option.
- Seek dog-friendly alternatives: Explore dog-friendly establishments, parks, or activities that allow you to spend quality time with your dog without compromising their safety.
- Plan ahead: If you must bring your dog along, plan your trips during cooler parts of the day and consider parking in shaded areas. Ensure you have a plan in place to never leave your dog unattended in the car.
- Keep essentials on hand: Always carry a portable water bowl and fresh, cold water in your car to ensure your dog's comfort and hydration.
- Spread awareness: Educate fellow dog guardians and community members about the risks of leaving dogs unattended in cars. By raising awareness, we can collectively strive for safer practices.
Conclusion
As loving dog guardians, it is our responsibility to prioritize the well-being of our canine companions. Understanding the dangers of leaving dogs unattended in hot cars, regardless of the external temperature, is paramount. By staying informed, planning ahead, taking preventive measures, and using an extremely conservative approach to “safe car temperature” we can ensure the safety and happiness of our beloved four-legged friends. Let's work together to spread awareness and make informed decisions.
Note: The information in this article is based on research and insights available at the time of writing. For expert advice, please refer to heatkills.us and consult with a qualified veterinarian.
* Dogs do have sweat glands, but their sweat glands function differently from those of humans. Dogs have two types of sweat glands: merocrine sweat glands and apocrine sweat glands.
Merocrine Sweat Glands: Dogs have merocrine sweat glands located in their paw pads. These sweat glands are responsible for producing a watery sweat that helps with cooling the body. When dogs walk on a hot surface or engage in physical activity, these sweat glands release moisture, which evaporates and helps regulate their body temperature.
Apocrine Sweat Glands: Unlike humans, dogs have a greater number of apocrine sweat glands, which are found in areas such as the armpits and groin region. However, these glands are not involved in thermoregulation. Instead, they produce a thick, oily substance that contributes to the unique scent of individual dogs. The apocrine sweat glands are associated with pheromone production and play a role in communication and social bonding among dogs.
Although dogs possess sweat glands, their primary method of cooling down is through panting. Panting helps dogs release excess heat by rapidly evaporating moisture from their respiratory tract and moist surfaces, such as their tongue and nasal passages.
