The region of Hurr Nor is
Jazzper 's now
Though I can tell you about Horror Island what it was RP'ed like before I sold the region.
I think in RP, we always roleplayed it as a warm area. The winds blew warm, and the rains were all the more stormy. I remember one time we roleplayed the rain and wind and I as DM made it happen so that the people on the island felt unsafe to be out in the open and unsafe under the trees as well, afraid a branch might fall off. That kind of storm. (Which eventually scared them into the caves, where the savages were living too).
There was a swamp on the island, due to the warm weather and impermeable soil in the center of the island. There were fire-flies when there was a night without wind or rain. There were swamp turtles on the island too. Realistically, the water on the island should have been salty or brackish at best, but a swamp is scary and I had no idea how to make a mangrove on that scale, so it happened to be a stinky swamp in the end.
Let me think... there were butterflies too. But of course only when the weather allowed them. There were all kinds of slimy creatures in the caves. Snails, frogs, newts, cave-eels, other fish. There were pheasants and other big birds (also doesn't make sense realistically for them to be in a coastal area I believe, but the savages need to eat).
The population lived in the caves because of the harsh storms and their skills at building a home never reached further than a quick hut. As a matter of fact, there were only two huts on the entire island, which were built over an entrance of one of the caves, which the savages presumably used as an outpost if they'd go hunting on the island or fishing at the shores.
There was also some RP on an island to the south, which was very similar. Hot weather, rainstorms and often lightning. If I remember anything more I'll let you know. Otherwise everyone who went to the horror events can also tell you about it