80 degrees outside, inside of the car 102 to 120 degrees even with the windows cracked. Car works like a green house, trapping the sun's heat. Dogs can only withstand a body temperature of 107 to 108 before suffering brain damage or even death.
Do not leave a dog in a car during the hot summer months.
Keep dogs cool with keeping the pads of their feet wet.
Allowing enough fresh drinking water and shade. Be sure water can not be spilled.
Keep a pool of fresh water for the dogs to have an opportunity to wet their bellies.