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[Stemo]

The outside temp gauge in my car says 16 degrees C. The thermometer in my garden says 15 degrees C. But it's not. The wind is keeping it well down. In fact, it's bleedin cold out there in the wind.
So....why doesn't the wind cool down the gauges so that they read the actual temperature?

[Field Marshal Dr. Opti]

Dunno.

[Stemo]

Dunno.

Me neither. 

[TheBoy]

Because temps are supposed to be taken out of sunlight and chill, thus the sensor is often mostly protected from these elements.

[cleggy]

Is this all you've got to worry about. Get a hobby.

[Rog]

Is this all you've got to worry about. Get a hobby.

Yep . . .  . .

There I was trying to figure out the meaning of life and what it was all about, and then somebody comes along with a bigger problem 

[chrisgixer]

Esta. You need a puncture in your life.

[Entwood]

If you wrap some linen (an old hanky) around the base of the thermometer, and keep it damp (immerse a bit in water so capillary action keeps it damp) you have just made a "wet bulb" thermometer which will give you the true temperature the human skin feels taking into account the wind chill factor.

http://en.wikipedia.org/wiki/Wet-bulb_temperature

The temperature indicated by a "normal" thermometer is the "free air" temperature .. the actual temperature of the air molecules that surround it .. which is why it should be in the shade and out of the wind..

The temperature sensor on your car will be that temperature if the car has not been moved for a while and was parked in the shade .. if you are moving it is affected by airflow, if parked in the sun it will be affected by the body temperature of the car

[pscocoa]

The outside temp gauge in my car says 16 degrees C. The thermometer in my garden says 15 degrees C. But it's not. The wind is keeping it well down. In fact, it's bleedin cold out there in the wind.
So....why doesn't the wind cool down the gauges so that they read the actual temperature?

you are the world's foremost authority on wind so why bother clever people?

[Rods2]

As Entwood says the bulb is dry, when moisture evaporates, it lowers the temperature, so this is what the wet bulb does. But also the thermometer will be about the same temperature (with any difference being a temperature change lag) as the air. Your body is warmer, so the air movement will speed up heat loss, where the warm boundary air close to your skin will be replaced by cooler ambient air and also your body evaporates water which will increases the humidity of the warm boundary layer, when it is replaced by this cooler dryer air, evaporation will slow down as the air is cooler, but will still be there.

[Stemo]

Thank you Nigel and Rod. The rest of you can piss off.   

[Rog]

Thank you Nigel and Rod. The rest of you can piss off.   

Oh, ok

I'll go back to finding a cure for cancer then . . . . . 

[Sir Tigger KC]

The 'wet bulb' principle can also be used to make a 'bush fridge'. 

So say you're out in the bush and it's so hot that your ice has melted and your beer is warm.   

Take a sock, soak in water, slip your can of beer in the sock and hang in a tree. By the time the sock has dried, the beer will be chilled!   

[Steve B]

Will remember that tip for the next time im out in the bush then. Brill tip   

[pscocoa]

The OP got excited at the talk of wrapping a hanky round his thermometer