There is a point in having small degrees, in that small fluctuations in the weather are more noticeable. I can say that the weather will be in the 60s today, an

There is a point in having small degrees, in that small fluctuations in the weather are more noticeable. I can say that the weather will be in the 60s today, and people will know what I mean, but saying it will be in the 20s today (in celcius) offers a much larger range of weathers to be had. Also, you can tell just as easily if something melts using Fahrenheit, you check whether it's above or below 32. Sure, it might seem a little arbitrary, but it's just as arbitrary as "36.6 C is healthy" or "cakes bake at 220", which people seem to remember just fine.