Want some more proof as to why you should never leave kids or pets alone in your car on a hot day? Take a look at this experiment from KTVB in Boise. They baked cookies inside a car.
They placed refrigerated cookie dough on the dashboard at about noon when it was 95 degrees. It didn't take long for the cookies to flatten out and start baking. By 3 p.m., with temperatures above 100 degrees, the cookies were baked through. By 5:45 p.m., the cookies were very crispy, even overcooked.