How Hot Do Cars Get?

Have you ever noticed how hot it can get inside a car on a summer day — far hotter than it is outside? That's because a car acts like a greenhouse, trapping the sun's heat. A study by the Animal Protection Institute showed that even moderately warm temperatures outside can quickly lead to deadly temperatures inside a closed car.

The study compared an outside temperature of a shaded area with the inside of an automobile in three states: Fully closed; With four windows cracked; With two windows cracked. Inside temperatures were measured with an indoor/outdoor thermometer and an oven thermometer. All temperatures use the Fahrenheit scale. The outside temperature is listed first, and then the temperature reading from inside the car:

Inside Closed Automobile
82° > 109°
87° > 115°
98° > 119°

Inside Auto with 2 Windows Cracked
80° > 95°
88° > 105°
99° > 109°

Inside Auto with 4 Windows Cracked
88° > 105°
90° > 108°
101° > 115°