It’s Hot Enough To Bake Cookies In A Car?!

Waco, Texas (KWTX) - The inside of a car left out in the sun can get very hot very fast. But just how hot can it get in there? Our Meteorologists CD Finley and Brendan Jackson set out to answer that question by performing an experiment to see if they could bake cookies inside the First Alert Weather Explorer.

Cars heat up very quickly when they are left in the sun with the windows closed. After just 10 minutes, the temperature inside the car can jump by almost 20 degrees. In the next 10 minutes, the temperature inside can jump by another 10 degrees. On a 100 degree day, the air temperature inside the car can jump to over 140° in only an hour.

The reason that the inside of a car can heat up so fast is because of the glass windshield and windows. The glass in your car allows the sun’s rays to get through to the inside of your car where it is absorbed by the material in your seats and floors and dashboard. When the materials in your car try to radiate the heat back out, the glass does not let it pass through and traps it inside.

Different cars can heat up at different rates than others depending on what is inside the car. In cars with darker seats and dashboards the temperature of the air will heat up more than in cars with lighter colored upholstery. This is because darker colors absorb more heat from the sun and because of that they radiate more heat back out so more heat gets trapped inside the car.

The temperature was at 90° outside when the experiment began and the inside of the Weather Explorer was already about 120 degrees. The temperature only continued to climb from there, reaching as high as 170° after a few hours. The cookies were able to successfully bake in those temperatures, after a 5 hour stint on the dashboard of the First Alert Weather Explorer!

So the answer to our initial question - (how hot can it truly get inside of a car left outside in the heat?) - is VERY! So hot, that you CAN in fact bake some cookies inside the car! That is...if you have the patience to do so. Even then, we wouldn’t recommend eating those cookies either, as you would need the perfect kind of dough (the kind that is marked as safe to eat raw) and the perfect temperatures to kill any bacteria in the dough.

This experiment goes to show the exact reason that we always emphasize (especially in the summertime, but this rule goes year round too), NEVER, under ANY circumstances, leave a child or pet unattended in a car. If it is hot enough to bake cookies inside of a vehicle, it stands to reason that it is unsafe to leave your pets and/or your children unattended in a hot vehicle.

Other heat safety tips include:

- staying cool in the shade or air conditioning

- drinking plenty of water to stay hydrated

- wearing light colored/loose fitting clothing

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