Fahrenheit has such a weird base set.... The original scale items were 0 Degrees is Brine/Salt Water and 98.6 for life. I forget why Fahrenheit wanted it to be 98.6 but it wasn't 100% random, however life varies on it's temperature so it's really not a sound system...

That said, because Fahrenheit would be considered more exotic to most of the rest of the world, the Eorzean system would be based on it. That would mean most water freezes at 32 degrees. However, the real question is do they refer to degrees as degrees or something else? Also, what crazy Eorzean decided the temperature of life should be 98.6 degrees? Is there a committee of people who have unsuccessfully for 100 summers attempted to get everyone to attempt a more sensible system?