CHART A COURSE
When the players start talking about leaving town, direct them to this move. Use it to clarify their destination and how they intend to get there. If they have no ideas, prompt them to Know Things. Their route doesn't need to be perfectly clear something like, "We follow the tracks" is fine—but they should have some idea of where they're going and how they're going to get there.
Once they've established their destination and route, tell them as many of the following as make sense. Make your choices based on the seasons, the terrain, how well they know the area, the dangers that lurk there, the threats you've established and their grim portents. Don't worry so much about the order right now, and feel free to rephrase or tweak the wording. If it makes sense, add entirely new items.