However you want ... whatever makes the most sense for your story.
If the conflict is the smoke, Dramatica tells you what's causing it (the fire), but it doesn't restrict you in any way as to what the smoke looks like, which direction it blows in, what shape it takes, etc. All of that is storytelling.
Keep in mind that in an actual story there are a lot of feedback loops, though. For example, the Physics of building a bridge causes werewolf attacks because they're logging in the forbidden forest where the werewolves live. Now Self-interested parties begin to wonder if other legends about the forest are true and subvert the werewolf peace mission in order to Pursue the fabled lost treasure of the silver unicorn...
So the smoke from one fire often drives characters to start similar, related (by the storyform) fires. In my experience this happens naturally, as long as you remember to view your story points not just as sources of conflict but as drives.