[js2]

I've never lived anywhere in the U.S. that gets that cold, but in my experience, I don't think Americans say that much, but rather "below freezing" to mean below 0°C/32°F.

I happen to easily remember that 20°C = 68°F and usually use that when mapping the temperatures back and forth which works for the usual ranges where I've had to do so by just adding/subtracting 5/9 on each side.

I once translated literally on the run (running the Boston marathon) for a foreigner who asked about the temperature and got a Fahrenheit response.

When I've been in other countries that use C, I've always had to translate from C back to F in my head to make sense of the temperature. The longest I've ever been any place outside the US is 10 days, and that hasn't been enough time for me to get a feel of what temps are in C.

[aksss]

> I've never lived anywhere in the US that gets that cold, but in my experience [which we've established is none], I don't think Americans say that much.

It's a thing in Northern climes where the temperatures can get that cold. Everyone living in such places will know the term and you'll hear it frequently when talking about the weather or listening to weather forcasts.

[bigiain]

Where I come from, "It's fucking freezing!" colloquially means "under 10C". Because that's the lower edge of our "normal" climate here, so our houses are not insulated well for temps below that and central heating is rare because it's rarely needed. We also tend to not have a wardrobe with much that's suitable for temps down below 10C, unless you happen to have ski gear or winter motorcycling gear or whatever. (I've got one bike jacket which is too warm to wear at temps much above 10 or 15C - it gets very little use, in spite of me _really_ liking it...)

[bigiain]

I'm the opposite way. I understand the world in C.

I've got a few references in my head -40C = -40F (because magic), 0C = 32F (water freezing), 37C = just under 99F which I'm mostly approximate to 100F (body temp). 92C ~= 198F (espresso brewing temp), and 100C ~= 212F (boiling).

I use those to interpolate other F temps to whatever precision I need.

Brewing espresso I care about maybe half a degree C precision. Deciding what clothes to wear I only need to be within maybe 5 degrees C (so to me, 60F is "about 20% under halfway between 100F/37C and 32F/0C, so ~20% less than 18.5C - call it 15 = cold enough to take a jacket). For cooking I don't need to care to much about anything better +-20 degrees.