Where is Torils equator?
Looking at the map in F&A, we can see that the equator runs through the southern part of Maztica (just below the published map), through the northern portion of Zakhara, and through the southern reaches of Kara-Tur. It falls a little south of Nimbral (I think that’s Nimbral) and well south of Chult. Abeir-Toril, according to every published source, is roughly equivalent in size to Earth. However, part of what determines the size of the tropics and the intensity of the seasons is whether or not it has the same axial tilt. Since there are very definite summers and winters, I’d say the axial tilt is the same or perhaps even a little greater (23.5-25 degrees, as a ballpark guess). Note also, from the same map, that even including Maztica we’ve only seen about a third of the surface area of Toril. There’s a LOT of room for more lands to explore, to the west of Maztica and/or the east of Kara-Tur (as well as to the south of everything).