The Dangers of Hot Cars for Dogs

With hot weather forecast across the country this weekend, motorists are urged to not leave their beloved pet dogs in cars for any me.

The experts at and its sister site have been exploring the changing internal temperatures of a car with different temperatures outside.

And the stark message is dogs can die and suffer if left in a vehicle even in what might be considered mildly warm weather.

This is because the temperature inside increases the longer a dog is left on its own and that is a huge risk to a pet’s health and wellbeing.

To illustrate, 21˚C outside can see a car’s internal temperature shoot up to over 45 ˚C in just an hour – more than double what it was at the start.

For humans, high environmental temperatures can be dangerous to your body. In the range of 32˚ and 40˚C, you can experience heat cramps and exhaustion. Between 40˚ and 54˚C, heat exhaustion is more likely. Dogs, with layers of warm fur to account for, who learn to pant to keep cool, therefore face grave danger in any raised temperature.

Tim Alcock from said: “Animal welfare messages have been extremely effective in recent years educating people not to leave their dogs in cars on a hot day due to the risks of overheating.

“But the simple truth is even on what might seem a mild or warm day where temperatures are around the 20˚C mark, the internal temperature of a car can quickly multiply to dangerous and fatal levels.

“We are therefore urging motorists to NEVER leave a dog unattended, whether wind, rain or shine. Don’t make that ‘quick dash to the shops’ result in a fatal error which will stay with you forever by leaving your pet on its own in a car and potentially at risk.

“Instead, practice good habits by always ensuring that when you leave the car to run an errand, if your dog has been traveling with you, it also goes with you.”

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The following temperature changes can occur inside a car:

Time in minutes Outside temp in C


Outside temp in C


Outside temp in C


Outside temp in C


Outside temp in C


Outside temp in C


0 (Internal temp in C) 



23.9 26.7 29.4 32.2 35
10 31.7 34.4 37.2 40 42.8 45.6
20 37.2 40 42.8 45.6 48.3 51.1
30 40 42.8 45.6 48.3 51.1 53.9
40 42.2 45 47.8 50.6 53.3 56.1
50 43.9 46.7 49.4 52.2 55 57.8
60 45 47.8 50.6 53.3 56.1 58.9
>60 46.1 48.9 51.7 54.4 57.2 60