Has anybody done any checks to see how accurate their thermometer is? On our Saturday GSM run north of Baton Rouge, we showed 108 at one point. I have never seen it that hot, but it was VERY hot. The weather channel said 102 (a 37-year record).

 

Mine will display up to 10-12 degrees hotter than actual if the car has been
sitting in the sun for a while, but if in the shade, or after driving a few miles,
it's pretty darn accurate.

 

Keep in mind the heat from the blacktop and roadsurface baking in the sun may be warmer and helping to influence the temperature a few inches off the ground compared to taking the temperature a few feet higher...

 

I have found that the thermometer is great at getting the road (or track) temp...

That is during the summer, the temp on the highways baking in the sun is 5-15F hotter than the shady back road twisties.

The moral of the story is take the back roads as much as possible

 

"Official" temps that you hear on the news and such are always the temp in the shade. Since your MINI is more than likely in the sun most of the time, the themometer will show a higher temp than what they say on the news.

 

That, plus heat reflecting off the road and body panels and traffic-generated heat.

 

I've found mine to be really accurate when on the move, but as others pointed out, when parked it tends to show a bit hot till I get rolling.

 

Never heard that before. In many places the official temps are at the local airports. Where I live I know it isn't the temp in the shade as I have seen their weather recording equipment and there is no shade anywhere near it.

The last several days where I live have been 100+ degrees. My MINI has never shown anything higher than 99. I was wondering if that was as high as it would register. It was hot enough yesterday the the cover over my convertible top buttons partially melted and warped in the sun(top was open). Official readings according to the local news was 102 degrees in that town. A town close to where we were had 104 degrees. Still, the temp on the MINI only showed 99.

 

"official" temperature measurements (such as collected by meteorologists) are in the shade where they can measure air temperature. The device itself is shaded as to minimize the impact of radiation on the sensor (secondary "blackbody" radiation being several orders of magnitude less than direct solar radiation).
However, reflected radiation from the ground tends to make air temperature closer to the ground a little warmer than higher up so that a sensor on your car at 2 feet will probably be a little warmer than one at 6 feet (the height found at most measuring stations).
I do not know where the temperature sensor is on my mini but on my Saab it was behind the front license plate. After sitting in the sun, it was often 10 to 15 degrees above what the local weather station indicated but after a few minutes driving, it was usually pretty close.

 

on the first gen MINI's the thermometer is behind the lower grill on the front bumper. right behind it is the ac condensor and the radiator.

 

Thanks for the explanation.

Still wondering why my thermometer only registers 99(so far as I can tell).

 

I've compared mine to thermometers on bank signs and that kind of thing and found it to be within 2-3 degrees. Of course how accurate they are is another question but still...

 

+1.

I've had the temp go up several degrees immediately after transitioning from a cement to asphalt surface.

 

Is the location of the sensor the same on all the model years? And why does it consistently read 30 degrees cooler than the actual air temperature after washing the car?

 

I *think* it's pretty damn accurate. On Monday coming back from MITM we were cruising through Utah, Arizona, and Nevada, and the thermometer was reading 111. I believe it. It's the first time that the temperature has forced me to pull over, put the top up, and turn on the A/C. I shamed 'vert owners everywhere, but I couldn't take it anymore.