Weather prediction in the mountains can save your life! There are signs that a traveler can observe that will give some indication of what the weather will be doing in the future. Some examples are observing rings around the sun or moon; those rings indicate moisture and are cirrostratus clouds that are often associated with warm weather fronts. These rings often signal a storm approaching within 72 hours. A red western horizon at sunrise signals clouds approaching that day. Observing the various cloud formations are used in prediction as well. Although it might be fun to have a bunch of these indicators in-game, it would be much more straight forward to abstract them to a new skill, "Predict Weather". That kind of passive skill might present its own problems however, because it is not really like any of the other skills, which are more active. So perhaps the best solution to get weather prediction into the game would be to add a new item, the Barometer. It would be simple to use; just pull it out and take note of the reading. If you notice that the air pressure is trending down over time, then it is likely that a storm is approaching. Gaining elevation will also cause a drop in pressure, so the player would need to take that into account. A quick and large drop in air pressure, well, hold onto your hat!