Taken from another site:
The American Society for the Prevention of Cruelty to Animals warns that dogs left in parked cars can die of heatstroke.
On a 60-degree day, a parked car can reach 100 degrees, according to a study from Stanford University. Leaving windows open a few inches does not help. In only a short amount of time, a dog with a high body temperature can suffer critical damage to his nervous system, heart, liver and brain, often leading to death.
Dogs overheat more easily than people because dogs do not sweat, they pant to cool down. Don't leave dogs in cars for any amount of time | SeacoastOnline.com
I don't think it's a good idea to leave your dog in a car, I wouldn't leave a child, I wouldn't leave a dog. You guys see this thread, it's an application for phones to report animal abuse.
http://www.yorkietalk.com/forums/gen...dog-abuse.html