When is it too Hot to Leave Your Dog in the Car?
70 Degrees & Above - Leave Your Dog at Home
When temperatures outside reach 70 degrees, the temp in your car rises to about 100 degrees. Even with the windows "cracked", your car turns into an oven. Dogs can sustain brain damage or even die from heatstroke in just 15 minutes. Beating the heat is extra tough for dogs because they can only cool themselves by panting and by sweating through their paw pads.
As the temps rise, the danger grows:
So, if it's above 70 degrees, leave your dog at home.