If you’ve ever looked at your car’s outside temperature display while idling in traffic on a nice summer day, you've probably noticed the display can vary quite a bit from reality. As Lifehacker explains, that’s because the sensor telling your car’s computer the temperature might not be in the best spot.
Usually placed in the front fascia, behind the grille, the ambient air sensor will pick up the heat from hot asphalt or concrete. That’s why the temperature sent to your instrument cluster or media screen often changes when you finally get out of rush-hour traffic or to a location where the pavement is cooler.
The sensor's low location puts it close to roadways, which are excellent at absorbing, storing and radiating heat from the sun. When the sun’s energy is blocked or you can get enough fresh air rushing over the sensor, that’s when you’ll get a more accurate reading of the outside temperature. The Weather Channel makes it clear that this situation isn’t exclusive to warm climates or seasons, but the sun can make you unaware of black ice-inducing temperatures on roadways.
You should also note, if you just got in your car, you should have a good grasp on what it was like when you were outside moments before. We hope.
