If you have one thermometer, you know what the temperature is. If you have more than one, you don’t. That was the situation this morning when I went to look. The new “weather station” I got for Christmas told me it was -30C (-22F). My old weather station had the temperature at -28C (-18F). When I went to the old style thermometer outside the kitchen window the reading was -27C (-17F)and the window thermometer upstairs gave me -28C.
The two window thermometers are just a few inches from the windows which probably radiate a bit of heat outside. My old weather station gets its information from a unit upstairs on the balcony, so that may be somewhat warmer than my new weather station that registers from a fence post by the open pasture so that may be why it shows the coldest temperature.
I guess knowing the exact temperature is not that important, its enough to know that it is damn cold outside.
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