Every year, children and pets die in hot cars. Regardless of information campaigns, people keep leaving babies and dogs in cars, and Texas has topped the number of fatalities around the USA for the past twenty years.
Texas Corporal Jessie Peterson made an experiment, and posted a video to YouTube of himself staying inside his parked patrol car in the sun. He held out for 30 minutes, and had to leave the car to recover. When the temperature outside nears 100 degrees, the temperature inside the car quickly jumps up to as high as 170 degrees.
Heat-related injuries can cause organ failures, seizures, and hallucinations, and if the exposure to heat remains, death.
Peterson is a trained officer in good shape, and did his experiment in a safe environment with help nearby. This is not something that should be tried at home. And please, do not leave your children or your pets in the car.
To read more about the experiment, follow this link.