How Hot Does a Car Get in the Sun: Understanding the Extreme Heat Inside a Vehicle

The temperature inside a car can rise significantly when parked in the sun. On a sunny day, the interior temperature of a car can increase by 16 to 28 degrees Celsius (30 to 50 degrees Fahrenheit) within just 30 minutes, even if the outside temperature is only a few degrees above the baseline. For example, if the outside temperature is 85°F (29°C), the inside of the car could reach 115°F to 135°F (46°C to 57°C) inside that time. This effect is due to the greenhouse effect, where sunlight enters the car, warms the surfaces inside, and the heat is trapped, preventing it from escaping.

Key Factors Influencing Interior Temperatures

Several factors contribute to how hot a car gets inside:

Outside Temperature

Higher outside temperatures lead to higher interior temperatures. As a general rule, for every 5°C (9°F) increase in outdoor temperature, the interior temperature can rise by 6.3°C (11.3°F) in a short period.

Color and Material

Dark colors and certain materials can absorb more heat. A dark-colored car will heat up faster and to a higher temperature than a light-colored car. The materials inside the car, such as leather seats and dark carpeting, can also absorb and retain heat more effectively.

Windows

The types of windows can significantly impact heat absorption:

Tinted Windows: Tinted windows can reduce heat buildup and help keep the interior cooler. However, they can also affect the visibility and may not be suitable in all situations. Clear Glass: Clear windows allow more heat to enter the car, contributing to a higher interior temperature.

Ventilation

Ventilation options can help reduce heat buildup:

Open Windows: Opening windows, especially if the car is on a slight incline, can help cool the car by allowing air to enter at the bottom and escape at the top. Sunroofs: Sunroofs provide another ventilation option, allowing fresh air to enter the car. A/C: While air conditioning can effectively cool the car, it also consumes more fuel, leading to a potential increase in temperature outside the car.

Real-World Examples and Statistics

A thermometer in a truck has shown that it can be 130°F (54°C) or higher during the summer when the outside temperature is 100°F (38°C). In some regions, the inside of a car can heat up even more. For instance, in Phoenix, Arizona, on a 115°F (46°C) day, the inside of a closed car can approach 150°F (66°C). The engine coolant might reach around 212°F (100°C), which is the boiling point of water. Asphalt in the hot sun can be too hot to touch, and tires can become even hotter. Exhaust gasses can reach temperatures around 900°F (482°C), making them extremely dangerous.

Prevention and Safety Tips

To minimize heat buildup in a car:

Park in shaded areas: Whenever possible, park your car in a shaded area to reduce the amount of heat that enters the vehicle. Use sunshades: Installing sunshades on your windows can help block some of the sunlight from entering the car. Leave windows slightly open: Leaving windows slightly open can help with ventilation and reduce heat buildup, but do ensure that the windows are secure to prevent any potential accidents.

Remember, as a rule of thumb, it is not safe to hold an object over 130°F (54°C) for extended periods. In extreme cases, the temperatures inside a car can exceed this limit, especially in hot climates.

Conclusion

The heat inside a car can be a serious issue, especially in hot climates. Understanding the factors that contribute to the rise in interior temperatures and taking preventive measures can help keep you and your passengers comfortable and safe during hot weather. By following these tips, you can significantly reduce the risk of heat-related issues and ensure a safer driving experience.