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So on my way home from hockey last night at 1am this is what my truck said. Weather app said it was only -3 and deck thermometer said it was -10.
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Who do you believe?
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So on my way home from hockey last night at 1am this is what my truck said. Weather app said it was only -3 and deck thermometer said it was -10.
I on occasion used to do performance testing of power plants, a wrong temp just off by a degree can impact plant efficiency by a lot. In order to improve our accuracy we sometime use multiple temperature measuring devices. I have routinely used 8 sensors to measure turbine inlet air temperature and then use statistics to get the results super accurate. We had to use thermometers calibrated to known standards. After calibration we would get a certificate that showed the as received, and then once the unit was calibrated to known standard we would get and as tested value with an instrument accuracy.
Unless the accuracy is stated on a thermometer its pretty well useless for testing purposes.
Realistically local microclimate can make a big difference. I live on hill with river valley down at the bottom. This drains areas farther north and has some wide areas with radiational cooling. On a clear cold night, cold air sinks and runs down the valley. I routinely can see a 5 to 10 degrees difference in temps from my house to the valley.
I wouldnt trust an AP as you dont know where the measurement location is. The house thermometer could be heated up slightly by the house its attached to or some local conditions and I expect the truck thermometer is not an expensive piece of equipment. RTDs and thermocouples are pretty precise and you can do a quick calibration by dipping them in boiling water and a glass of water full of ice. They are fairly linear so you can figure out the real temp even if the equipment you use to read them has some bias.
Unless the accuracy is stated on a thermometer its pretty well useless for testing purposes.
Realistically local microclimate can make a big difference. I live on hill with river valley down at the bottom. This drains areas farther north and has some wide areas with radiational cooling. On a clear cold night, cold air sinks and runs down the valley. I routinely can see a 5 to 10 degrees difference in temps from my house to the valley.
I wouldnt trust an AP as you dont know where the measurement location is. The house thermometer could be heated up slightly by the house its attached to or some local conditions and I expect the truck thermometer is not an expensive piece of equipment. RTDs and thermocouples are pretty precise and you can do a quick calibration by dipping them in boiling water and a glass of water full of ice. They are fairly linear so you can figure out the real temp even if the equipment you use to read them has some bias.
Many weather apps take local readings from "weather stations" installed by participating homeowners or schools. These are often not placed appropriately to get a reliable measurement. See if you can switch you app to use a nearby NOAA station. The measuring device on a car is a reliable, accurate device but subject to interference from sun, engine heat or road radiation. At night, it's probably more accurate than a $50 wifi device installed on your neighbor's chimney.
Microclimate can be a remarkable thing, once driving to work on a cold morning, I watched my car reading drop 10F over about a mile, then rise back closer to "official" temperature as I came out of a small valley. That may not have been an exact 10F, but it was a genuine local effect.
TE
Microclimate can be a remarkable thing, once driving to work on a cold morning, I watched my car reading drop 10F over about a mile, then rise back closer to "official" temperature as I came out of a small valley. That may not have been an exact 10F, but it was a genuine local effect.
TE
Microclimates are crazy. When the mirror registered -15 I was down at the bottom of a valley next to a river. When I pulled in my driveway it said -11. The hockey rink -3. The thermo was dropping and rising so fast I thought something was wrong with the thermometer. Seems to be more pronounced in the middle of the night
Ride a motorcycle for a while and you'll experience these micro-climates first hand.
I'm always amazed how much the temp can drop when you drop into a low area, especially if there's a stream along the road.
The thermometer in the mirror of my truck is one of my sources of entertainment, especially in summer. We try to go without AC if we can and I smile when I see the temps drop 10 deg. F between my work in town and our house just a few miles outside of town.
I'm always amazed how much the temp can drop when you drop into a low area, especially if there's a stream along the road.
The thermometer in the mirror of my truck is one of my sources of entertainment, especially in summer. We try to go without AC if we can and I smile when I see the temps drop 10 deg. F between my work in town and our house just a few miles outside of town.
sportbikerider78
Minister of Fire
Totally.. We have a little valley here (very small) on my way back from work. You dip down into it and for about 400 feet the temp must drop 10 degrees. Really nice on a hot day.
I always rip it up to about 110mph,,then it feels like 20.
sportbikerider78
Minister of Fire
I have a 2004 GSXR 750 that I rebuilt from a total. It's not pretty, but it is 100% reliable and I love it.
My 2 little ones, home, and job have been my priority the past 5 years...but I'm getting that itch pretty bad to start regular riding again.
JRHAWK9
Minister of Fire
This is where we live. It's in a lower part of the road near a stream in the middle of the woods. I have my temp sensor for my gauge hanging on a tree near the stream. It's always colder here than what the online places say, however, (broken link removed) online one seems to be the closest and the most consistent to what we see at our house.
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