Kind of a tangent, but I still firmly believe that for Earth weather conditions, Fahrenheit is a more intuitive scale. 0 is a really, really, really cold day and 100 is a really, really, really hot day. 50 degrees is neither especially warm nor especially chilly, 70 degrees is warm, 30 degrees is chilly, 20 and below are truly cold, 80 and above are truly hot, and if you go into negative numbers or above 100 degrees than you're in the "extremes".
Cold and warm are relative. 0 for freezing / snowing and 100 for boiling gives you a much more understandable range. Honestly, US metrics don’t make any kind of sense anymore...
While it's true that 100C doesn't have any weather meaning, 0F being "very cold" isn't particularly objective. I just looked it up, and apparently 0F is only about -18C. Whether -18C is "very, very cold" depends a lot on where you're from and what you're used to. I'm Canadian and I certainly wouldn't characterize -18C as "very, very cold". -30C maybe. 0C has a fairly objective interpretation in terms of weather: it's the point at which puddles start to freeze into ice slicks.
Yes, they are relative. 0 for freezing and 100 for boiling works well for chemical reactions and cooking. 0 for extremely cold weather and 100 for extremely hot weather works well for knowing what to wear before going outside. Celsius requires smaller numbers with decimals for similar weather precision.
