A dog's age and health can also be a factor in how well he handles extreme temps. When the outside temperature is 70 degrees, a car can heat up to 89 degrees in just 10 minutes, and to 104 in 30 minutes. At 80 degrees outside, you're looking at 99 degrees inside a vehicle in 10 minutes and 114 in 30 minutes.Aug 15, 2016read more >>