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#6,041
You do know that 0F = almost -18C right?

The freezing point of a specific salt based solution = 0F
Starting point of fever = 100F

Triple point of water = 0C
Boiling point of water (1 atm pressure) = 100C

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-7C here, about 19.4F.
 
#6,046
-13C this morning.

I like this picture.
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Here's a bit of text.
https://en.wikipedia.org/wiki/Fahrenheit
Fahrenheit proposed his temperature scale in 1724, basing it on two reference points of temperature. In his initial scale (which is not the final Fahrenheit scale), the zero point was determined by placing the thermometer in "a mixture of ice, water, and salis Armoniaci[16] [transl. ammonium chloride] or even sea salt".[17] This combination forms a eutectic system which stabilizes its temperature automatically: 0 °F was defined to be that stable temperature. A second point, 96 degrees, was approximately the human body's temperature (sanguine hominis sani, the blood of a healthy person).[17] A third point, 32 degrees, was marked as being the temperature of ice and water "without the aforementioned salts".[17]

According to a German story, Fahrenheit actually chose the lowest air temperature measured in his hometown Danzig (Gdańsk, Poland) in winter 1708-09 as 0 °F, and only later had the need to be able to make this value reproducible using brine.[18]

According to a letter Fahrenheit wrote to his friend Herman Boerhaave,[19] his scale was built on the work of Ole Rømer, whom he had met earlier. In Rømer's scale, brine freezes at zero, water freezes and melts at 7.5 degrees, body temperature is 22.5, and water boils at 60 degrees. Fahrenheit multiplied each value by four in order to eliminate fractions and make the scale more fine-grained. He then re-calibrated his scale using the melting point of ice and normal human body temperature (which were at 30 and 90 degrees); he adjusted the scale so that the melting point of ice would be 32 degrees and body temperature 96 degrees, so that 64 intervals would separate the two, allowing him to mark degree lines on his instruments by simply bisecting the interval six times (since 64 is 2 to the sixth power).[20][21]

Fahrenheit soon after observed that water boils at about 212 degrees using this scale.[22] The use of the freezing and boiling points of water as thermometer fixed reference points became popular following the work of Anders Celsius and these fixed points were adopted by a committee of the Royal Society led by Henry Cavendish in 1776.[23] Under this system, the Fahrenheit scale is redefined slightly so that the freezing point of water was exactly 32 °F, and the boiling point was exactly 212 °F or 180 degrees higher. It is for this reason that normal human body temperature is approximately 98.6° (oral temperature) on the revised scale (whereas it was 90° on Fahrenheit's multiplication of Rømer, and 96° on his original scale).[24]

In the present-day Fahrenheit scale, 0 °F no longer corresponds to the eutectic temperature of ammonium chloride brine as described above. Instead, that eutectic is at approximately 4 °F on the final Fahrenheit scale.[25]

The Rankine temperature scale was based upon the Fahrenheit temperature scale, with its zero representing absolute zero instead.
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#6,048
Continuous rain all day. Sump pump under the house cycling. Field between neighbor's house and adjacent road flooded - 1st time seeing that. If those rabbits that live in the blackberry bushes are hibernating, they're going to be in for a rude awakening, as their burrows flood. Our small pooch has a hard time when the weather's like this; owner reluctant, he's reluctant, wet, cold, miserable outside.
 
#6,050
I leave my Christmas lights out until early January. Today was the right day to put them away. Seems like Mother Nature has other plans. The cords that are covered in snow are locked in there due to the freeze-thaw cycle that has happened a few times since the snow began falling a couple of weeks ago. Just not in the mood to guess where the cord actually is and smash through the snow to get at them. I think I'll go make eggnog and watch the snow fall yet again. I thought I lived in Vancouver? Apparently I live in Canada.
 
#6,060
Fast Eddie D said:
We had freezing rain last night...
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Ditto - freezing rain that coated the snow on the ground in a layer of ice as it fell.

It's warmed up during the day, but it has been raining cats and dogs for hours. The blueberry fields on both sides of Hwy 15 in Surrey were under a couple of feet of muddy water on my way to work this morning. I hope BC isn't in for yet another bout of disastrous flooding.

The weather in BC has gone quite mad this year, and it is entirely the fault of us humans. We poked the sleeping bear one too many times.

Gnobuddy
 
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