I think that, given the level of control most flue-curing chambers (including commercial ones) have over temp and ventilation, it probably makes little difference.I plugged the numbers from the chart without rh into an rh calculator the other day and it came up with different numbers.
I don't know how much it matters
If we take Winston Salem, North Carolina as ground zero for flue-curing in the US, the elevation is 970 feet. Within the range of 55 to 100ºF for outdoor temperature, the atmospheric pressure is ~0.97 atm. This would lower the vapor pressure required to evaporate moisture from the wick of the wet bulb (causing it to display a lower temp), when compared to sea level (~1.0 atm). What is the impact on RH? I can't think it through. It makes my brain hurt.
Bob



