JACKSONVILLE, Fla. — You just turned off your television after watching First Coast News at Noon and you walk outside to turn on your car. The dashboard reads 102F!
"But Meteorologist Lauren Rautenkranz just told me it was 'only' 94F right now! What in the world?"
Chances are this scenario has played out before for you in real life in some form or fashion. Your car - new or old - shows a dashboard temperature that's way hotter than what it actually is. Most of the time these readings are incorrect and here's why.
Your car thermometer isn't like a normal thermometer. Instead of measuring the temperature with mercury, cars use electrical current to measure changes in temperature.
In a car, the thermometer (also known as a "thermistor") can be found behind the grill in front of the car, under the back or front bumper, or even on the side view mirrors. The problem lies right there - your car's temperature reading is coming from an unusually hot location surrounded by metal and the steamy asphalt.
Heat radiates up from the road and cars pick up that excess heat. An example would be getting a temperature reading from a big room next to the fireplace.
Now, this doesn't mean you can't use your dashboard temperature as a guide for how hot it is outside. When it isn't terribly hot out or after you've been driving for some time, there's less heat radiation and the reading will be more accurate.
Thank goodness we don't have to worry about freezing temperatures and precipitation too often here across the First Coast. In places that do, it can be tough to determine road conditions - if they're slick or icy - since these car thermistors aren't sensitive enough to distinguish between differences of one-degree.