Would it be possible for the engine to have season/month specific weather, like two months of minor and major raining? Also, the npcs would recognize what month it is and wish others good Tamrielic holidays and whatnot. If it was possible to have actual winter and summer, some loot and dungeons could be accessed only during certain months when the nature allows it. It would be really immersing and you would actually have to pass the time in-game and not have access to every quest or dungeon right away.

"There's a nip in the air, cold won't be good for my crops, never is"

Yeah...

We might need a little more than that. I like your idea.

I'm actually not sure about seasons, since they don't seem to really exist in either Cyrodiil or Skyrim. Not sure about Morrowind. And there is a perfectly logical explanation: Nirn might be a world with little or no axial tilt.

However, I do like the idea of the guards and passers-by mentioning harvests, festivals, holidays, and other annual events of Skyrim or Tamriel in general. It would make a richer game experience.

"Are you kidding? I came here to get away from the mountains and snow. You ever spent a winter in Skyrim? Or Bruma? Give me the Gold Coast any day." -Vigdis

Seasons are mentioned more than once, this is just my best example.