I'm a bit wary about the phrasing "from thin air". Why it can be look like for other people to be that way, I think it's more like extracting patterns from experience.
I think of it as a complex simulation and compare it to the approach of chaos theory.
To steer through a complex system of a lot of variables and parameters, where little variations and deviations can change the course and influence the outcome of events in a strong way. Ni might be a way to plot a route to your goals or destination, or at last keep track of it.