There's no in game option to change it.
American version
- Temperature is Fahrenheit
- AM/PM Clock 12:00 - 11:59 am/pm
European version
- Temperature is Celsius
- 24 Hour Clock 0:00 to 23:59
some stupid workaround:
Use an account tied to a different region, or change the consoles region.
EDIT :
It seems you have a hardcopy version of the game which mean there is nothing you can do except buying EU version of the game.
Easier Way :
(°F - 32) x 5/9 = °C
According to this article you should have gotten it on your first use of the amiibo. And if you did not put Epona into a stable you may not get her to summon again. It does not seem that there are any requirements for getting her to summon other than using the amiibo and it being the first time doing so, there are no indicators that using it at a specific point in the game changes how this works.
If the player has the Smash Bros. Series Link Amiibo, you can use the
Amiibo Rune to tap Link onto the NFC reader. While most other Amiibo
will summon a supply drop of items - the first time the Smash. Bros
Series Link is used, Epona will be summoned instead.
So my guess is, based off their explanation, is that you potentially summoned her and didn't notice and it may be stuck where you can't summon her again. Or you summoned her in the Plateau and you did not get to put her in a stable, thus she disappears.
However, if you wish to keep and ride Epona - you must register the
horse at a stable as soon as possible. If you summon Epona in a place
where you cannot get to a Stable, like on the Great Plateau, you will
be unable to summon Epona again, as using the Smash. Bros Series Link
Amiibo on other days will only summon standard supply drop items.
However; there is another article that mentions a fountain that may be of help to you.
The downside, of course, is that if Epona dies -- that's it. You
cannot respawn Epona by tapping the amiibo again after she dies, and
you will only be able to get her by restarting your game or by finding
the Horse God's Great Fairy Fountain.
So perhaps there is a chance you can get Epona back, based off of what that article says:
Unlocking this Great Fairy will allow you to bring any horse back to
life -- provided that it was registered, and that you have the means
to pay for it. Even legendary or rare horses can be brought back to
life at this fountain -- including Epona (provided you already
summoned her with an amiibo).
But since it doesn't seem like you registered her if she did spawn by chance, it may not work either. The only solution remaining after that, as far as I can tell, is restarting, which I can't imagine you want to do.
Best Answer
The map is topographic, meaning it's a top-down view of the land, using lines (and shading) to indicate height and degrees of elevation.
When the lines are close together, this indicates a sharp change in elevation. When they are further apart, it indicates a very slow change in elevation.
Each line indicates a certain level of elevation. While this map doesn't state this anywhere, you can assume that each line is drawn at a 10m interval, for example. Therefore, using the above image, the sharp change indicates a 30m change in elevation over a short distance (left to right), whereas the slow change indicates the same change in elevation, over a much longer distance. So, the left image is indicating a cliff face, and the right image is a rolling hill.
The other contributing factor is the shades used. Lighter areas are higher altitudes, and darker areas are lower altitudes.
Landmarks can be identified, based on their size and shape, and colour. For example, the ocean is blue - shallow water (that you are able to walk though) is a paler shade of blue, and water that you need to swim through is a deeper shade of blue; lava is red; buildings, large landmarks (like the Bokoblin dens or Leviathan Skeletons), trees and forests are generally a flat "bushy" texture, and paths are a solid flat colour, snaking through the land.
So, applying this knowledge to the map, we can see that the green arrow indicates a slow incline (lines are further apart), and the red arrow indicates a sharp incline (lines are closer together), a Bokoblin den is hidden away in an alcove surrounded by cliffs, and a few patches of trees are in the surrounding areas.
The only other primary factor for this is the map discovery. To uncover the map, you need to activate the Shiekah Towers in each region, to reveal the actual map. Locations that you dicscover will show up as icons on the map, but the background will still remain the original black and blue patterned background if you do not activate the Towers.
There is an online interactive map that you can use to compare with your own map, zoom in and move around to help you get a better understanding of where everything is, as well as quests, treasure, memories, koroks, and any other significant landmark might be.