You should never leave a dog alone in a parked car, even if the windows are cracked. Opening windows does not prevent dangerous temperature increases, and dogs can develop heatstroke in minutes. Heat, humidity, and poor airflow make cars unsafe environments for pets, and in many states, leaving a dog unattended in a vehicle is illegal.
Why Cracking a Window Isn’t Safe
It doesn’t have to be super hot outside for your car to heat up. The inside of a vehicle parked in 70-degree Fahrenheit weather can reach 100 degrees Fahrenheit in just 20 minutes. On very hot days, temperatures inside parked cars can climb to 140 degrees Fahrenheit in less than one hour.
According to the American Veterinary Medical Association (AVMA), studies have shown that cracking a window changes these figures very little. A parked car with the windows cracked heats up at almost the exact same rate as a car with the windows rolled up, putting pets in serious danger.
Why Dogs Overheat So Quickly
All dogs are susceptible to heatstroke, and every owner needs to be aware of their dogs’ limits. Some brachycephalic individuals (dogs that have relatively broad, short skulls), may be more sensitive to high heat and humidity. Owners should pay close attention to their breathing in warm or hot weather. Even dogs accustomed to exercise may overheat easily when exercising on hot days.
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Legal Risks of Leaving Dogs in Cars
Hundreds of pets die from car-related heat stroke each year. The issue is so important that 31 states have various laws restricting people from leaving their pets unattended in vehicles. Some laws ban the practice outright, while others protect law enforcement officers and citizens if they break into cars to rescue pets.
Other Risks for Dogs Riding in Vehicles
The best way to keep your dog safe in a moving vehicle is to use a harness, carrier, or crate. Without proper restraint, dogs can climb into your lap and restrict your view of traffic, move near and block the brake or accelerator pedal, and be seriously injured by an airbag or thrown into the windshield in the event of an accident or sudden stop. You can also for equipment that has been crash-tested and certified by the Center for Pet Safety.
Dogs who hang their heads out the open window are also at risk. Eye, ear, face, and mouth injuries from airborne objects or shrubs and branches can happen this way. Unrestrained dogs at open windows are in danger of falling out if there’s a collision or abrupt turn, and they may even decide to jump out if they see something they want to chase. A dog riding in the bed of a pickup truck is also at risk of being hit by airborne objects, falling from the truck, or jumping out.
So if you’re headed out to run errands that really don’t involve any fun activities for your dog, you might want to consider leaving them safely at home.
Safer Alternatives for Errands and Travel
If you need to run errands that don’t involve your dog, leaving them safely at home is the best choice. When travel is necessary:
- Bring another adult who can stay with your dog while the air conditioner runs
- Plan stops carefully so your dog is never left alone in the car
- Train your dog to wait calmly before exiting the vehicle to prevent sudden jumps
Teaching cues like “wait” and controlling exits can improve safety at rest stops and parking lots.
Key Takeaways
- Cracking windows does not keep a parked car safe for dogs.
- Cars can reach deadly temperatures in minutes, even on mild days.
- All dogs are at risk of heatstroke, with some more vulnerable than others.
- Leaving dogs in cars may be illegal and can carry serious consequences.
- Proper restraints and planning improve safety during travel.
* Originally posted by the American Kennel Club.