Does humid air rise? Will the cigars at the top of my humidor be more moist than the ones on the bottom? There seems to be a lot of confusion about these simple questions. But by placing multiple hygrometers inside a large humidor, I’ve observed that humid air DOES rise. This observation is confirmed by a more scientific approach in this online article:
This understanding explains a lot. If water vapor was heavier than air, evaporation could not occure. But this unscientific explanation is very general and doesn’t take into account things like temperature, elevation, and other factors that I am not even aware of. But for a cigar collector, this rather simple generalization is good enough. For consistant cigar humidification, we need to circulate the air in our storage units and rotate the cigars in our humidors.