Coming so soon after the flurry of conversation on the metric system (of which I had said I was done, but oh well), I had to laugh at this. Saying 'over 40°C' means 'hot', and makes a general point about temperatures in the 40s. Using 'over 104°F' makes it about that specific temperature in a way that the original didn't. When we converted to the metric system, a topic of note was soft versus hard conversions. A hard conversion is where you write 'add 226.8g of butter' in a recipe when you meant half a pound, a soft conversion would be to use 250g (a quarter of a kg) and adjust proportions of other ingredients to match. I always find it amusing when news items cite ridiculously precise measurements of things because they have made a hard conversion, and it's just as amusing whether that conversion is to or from SI.