Motorists are being urged to avoid leaving their dogs on their own in cars for any amount of time - regardless of the weather.
Experts 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.
When it is 21C outside, a car’s internal temperature can shoot up to over 45C in just an hour - more than double what it was at the start.
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For humans, high environmental temperatures can be dangerous to your body.
In the range of 32C and 40C, you can experience heat cramps and exhaustion, but when it reaches between 40C and 54C, heat exhaustion is more likely.
Dogs, with layers of warm fur to account for, who learn to pant to try to keep cool, therefore face grave danger in any sort of raised temperature.
A spokesperson for LeaseCar.uk, who carried out the research, 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 20C 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.”
What to do if you see a dog in a car on a warm day:
If the dog is showing any signs of heatstroke, you should immediately call 999.
A RSPCA statement reads: "If the dog's condition is critical, and the police haven't arrived yet, your instinct will be to break into the car to free them. But please be aware that this could be classed as criminal damage.
"You may need to defend your actions in court, so please be sure you're doing the right thing. Legally, you can commit damage if you believe the car owner would consent to it if they knew the dog was in danger.
"If you're sure you need to free the dog, tell the police what you intend to do and why. Take photos or videos of the dog. Are there any other witnesses? Take their names and telephone numbers.
"Don't be afraid to dial 999. If it's an emergency, we may not be able to get to you - and the dog - quickly enough.
"And as we have no powers of entry, we'd need to ask the police to help us rescue the dog. Don't worry - the police will soon let us know if the dog needs our help."
Do you have a dog story to share? Email paige.freshwater@reachplc.com.
