Shroud of the Avatar.
According to the developer, "As you know, we are working with a hex style map. One of the things we've done to streamline content development is to assign hexes with terrain presets, such as swamps, forests or mountains." Terrain will be endowed with "primary" characteristics that will allow simplified world building.
As for weather, the developer wants it "to look and feel real, while also having a meaningful impact on the player." The game will use it dynamically, as "evolving weather patterns... along with the day and night cycle, will be an important part of each scene. For example, perhaps a player can only approach a secured location under the cover of darkness, or maybe there is a rare herb that can only be gathered during a thunderous rainstorm."
Check out the dev diary in the video below.