There is one region in particular that used to be rather temperate, but has been suffering through severe winter-like weather conditions over the past year, imposed by the activity of certain NPCs.
So this means that if you're in Taslamar and decide to fly south past the mountains, you will probably encounter a winter-like storm. Similarly, if you're in Zhenshi and decide to fly west past the mountains, you will probably encounter a winter-like storm. Similarly, if you're in Uxmal and decide to fly southwest past the mountains, you will probably encounter a winter-like storm.
You probably know by now which region I'm referring to, especially since I'm the Ayamao KD.
These are extreme weather conditions here, but they are what they're supposed to be at the moment.....