SPCA staff talked to the owner but are concerned the dog hadn't been taken to the vet yet which could mean a prosecution.
Ms Ericsson said when they went to a call they waited as long as possible for the owner to come back. In extreme cases an SPCA inspector was legally entitled to break into a vehicle to free the animal.
"The owners just aren't thinking. When the weather is so hot, you're not doing your dog any favours taking it out for a ride. Leave the dog at home where there's shade and water."
Some people who'd left their dogs while they popped in for a quick drink with friends or even lunch just hadn't thought about the welfare of their dogs, she said.