European here! For me it's...
Celcius:
0 = Water freezes
100 = Water boils
Fahrenheit as far as I can tell:
~100 = Hot enough that it shows up on the news
~400-450 = Cooking, because our stove is in Fahrenheit for some unknown reason.
All other temperatures in F = no idea.
You can think of F as a “% hot” measurement for weather.
0 = no heat: getting dangerously cold for humans. 50 = half hot, half cold: wear long pants and a jacket. 75 = three quarters hot, getting close to t shirt weather. 100= fully hot: getting dangerous for humans.
Yes you can go over or under, but you can consider those to be extreme weather (120% hot!)
C is a measurement for water.
75 is only close to tshirt weather?
Acclimatization is a whole thing. I remember thinking 65F / 18C was cold once upon a time, then I moved north and now only bother putting on a jacket if it's below 40F / 5C or so (but now I start seriously suffering above 85F / 30 C where that used to be my ideal temp).
People who pretend certain temps are objectively not that cold or hot have never moved from one climate to another, I think. The person you replied to must be from a hot area.
I spent a week in the Rockies and when I got home, my house at 24°C was just too damn hot I just drank ice water and sat in my underwear.
Yep. I lived in the middle East and SE Asia combined for around 12 years, and while occasionally it was too much, in general I loved the heat and rarely said "its too hot", I moved back to the UK 3 years ago, in June. Hated it, was cold all the time. Now when it's more than 25c / 77F on a calm and clear day I'm boiling and can't sleep at night (barely anyone in the UK has ac at home).
Fahrenheit is designed for humans. Celsius is in love with distilled water at sea level. Kelvin and Rankine are actually useful in math, science, and engineering.
My wife told me to go look at the thermometer outside and the needle was pointing to 0. She asked "what temperature is it?" I said, "uh.. there isn't one."
This is pretty good! I'll keep this in mind next time I'm in the US.
Fahrenheit
0 = Well below freezing, about as cold as it gets anywhere that isn't frozen year-round. Dress like you're climbing Everest.
25 = Just below freezing, very cold but not record breaking anywhere people own snow shovels. Bulky jacket and gloves.
50 = Cold to cool, depending on your baseline. Put on a thick sweater or a jacket.
75 = Perfect, slightly above room temperature. T-shirt and shorts.
100 = About as hot as it gets anywhere that isn't a desert. Tank top and sunscreen, and stay in the shade.
Me setting my thermostat to 50 in winter:
The main Fahrenheit I know is -40F.
Mostly because its also -40C.
Why do I care about water boiling when we're talking about weather?
People contain water
If you are regularly encountering weather that is boiling the water in your body, you may want to consider moving to a nicer climate.
How frequently does the water in a human boil?
0 freezing
10 cold
20 nice
30 hot
Same the other way around. I (european) regularly read about "100 degrees weather" somewhere in the US and my first thought always is "damn, that's as hot as boiling water".
In the UK you think "Oh yeah, my great granny used to use those measurements!"
0 is freezing (32F)
10 is cold (50F)
20 is nice (68F)
30 is hot (86F)
Canadian here... in spring, 10C is shorts and t-shirt weather, eh?
Toronto is basically due east of where I live. 10C is pretty nice out. Hell, sometimes I don't wear a coat when its 0C
Yeah, if it's not super humid 0C can be pretty ok
Daytime 10c is shorts and tshirt. Nighttime 10c is shorts and light hoody.
40 is unbearable
50 is death, tar sticks to your shoes, why am I outside?
5 is cold 10 is fresh 20 is warm 25 is hot 30 is too fucking hot
Here's celcius
Water:
0° - freezes
100° - boils
Me:
10° - freezes
30° - boils
Why can't I be more like water?
You're 70% of the way there!
So you are neither Canadian nor Australian.
I talked with an american so i of course used ammo (9mm) as a scale
In Minnesota yes. In Florida no.
Well, double dumbass on you!
Cause 30C is warm but 39C is heat stroke. Bigger range than 80-89F (warm to really warm), 90-99F (hot to really hot), 100F+ (heat stroke hot).
In numerics we have decimal points for that :)
We don't even need that for weather. There's not that much of a difference between 21 and 22 C, and anyway with wind and shade you can quickly have a difference of a few degrees.
I very rarely hear anyone refer to air temperature with a decimal though.
Double it and add 32
Low 30s °C can either be okay or absolutely horribly hot depending on stuff like humidity, cloud coverage and wind.
Also what you're used to.
Australia? Normal day. Norway? Catastrophic.