How accurate is your external temperature gauge?

So with the temperatures now dropping here in Calgary I have noticed my external temperature gauge is upwards of 2 to 5 deg C out, it is always reading warmer that it actually is. Has anyone else seen this, can it be recalibrated or is it a trip to the dealer?

Off under what conditions? Car warmed up? Standing? Moving?

I have yet to find a car that didn't read high when warmed up and standing,due to it's own heat pooling around it. Reading off when cold (at external temp), then that's a real issue.

- Tim

Upshot: Know the conversion factor for one's car. Select one's "comfort reading". So relatively, IT is VERY ACCURATE !

As soon as one clamors for a "static official weather room" reading, the next thing on the agenda is what is it in the real world: like what is happening in and around ones car. So for example, if you (as in time) hack it on (whatever you hack it on) .....

Here is a case of TMI. On the computer screen of VW Touareg's (12 MY, in this example), tire pressure/s for each of 4 tires can be displayed. TP is affected by ambient temperature @ app +/-1 psi per 10 degrees (F in this example). It is affected by operation which can range between 4 to 9 psi, which by default can be 40 to 90 degrees. It also can be affected by sun and wind chill factors. Lastly the computer measurement has its own unknown error. So it would beg the question how many folks/tire shops use "calibrated" TP measurement devices, let alone calibrated temperature gauges? So for example the cheapie hand gauge I use is 1 psi difference from the VW T's computer reading.

I find it to be accurate enough. It does need time to adjust though so depending on the variables, just pulled out of my warm garage etc. I give it more or less time to adjust.

If I've bene driving for 5-10 miles I generally say it's good.

^^^this for me, as well.

Could be that the temperature of the road surface is elevated due to the sun heating the pavement.

hudsonian: Harrumph...I've never believed any thermometers on banks, businesses, etc. Just my opinion, of course!

tdiatlast said:

hudsonian: Harrumph...I've never believed any thermometers on banks, businesses, etc. Just my opinion, of course!

Click to expand...

Yeah those things are terrible. There Is a bank I drive past that's always 10f off the correct temp.

its always within 2 deg of my $500 home weather station. But not as accurate as the state plow trucks that have surface temperature readouts via IR sensors in the bumper that update twice a second

Since we're splitting hairs...

Quite frankly I couldn't care less what the display says. Hell I don't even need an OAT reading for that matter. If it's cold it's cold if it's hot it's hot. Not knowing the exact temp doesn't bother me.

jrm said:

its always within 2 deg of my $500 home weather station. But not as accurate as the state plow trucks that have surface temperature readouts via IR sensors in the bumper that update twice a second

Click to expand...

I'm kind of a weather junkie. What kind of home weather station costs $500? sounds pretty cool

jrm said:

its always within 2 deg of my $500 home weather station. But not as accurate as the state plow trucks that have surface temperature readouts via IR sensors in the bumper that update twice a second

Click to expand...

I've been considering a home weather station. Do you update to Wunderground or something similar?

mines working just fine

jrm said:

its always within 2 deg of my $500 home weather station. But not as accurate as the state plow trucks that have surface temperature readouts via IR sensors in the bumper that update twice a second

Click to expand...

ChadS99SVT said:

I'm kind of a weather junkie. What kind of home weather station costs $500? sounds pretty cool

Click to expand...

VeeDubTDI said:

I've been considering a home weather station. Do you update to Wunderground or something similar?

Click to expand...

I want a nice personal weather station too. What model do you have? Does it have a rain gauge?

I have the Davis Instruments 6152 Vantage Pro2 Wireless but there are many versions of that same station for less.

My father has this one:
http://weather.oregonscientific.com/products_lw301.asp
By far the best bang for the buck- holds historic Temp, wind, humidity and viewable on any modern phone or tablet- but it lacks the ability to show how much rain has fallen- only shows the rate that rain is currently falling in mm or in per hour
* correction, the mobile app doesn't have the ability to show amount of rain but a simple table top display that reads data from the same sensors for $65 extra sure does! Just ordered one for a gift