I store all my cigars at 12°C (53.6°F), wrapped airtight, regardless of anything.
For RH:
New cigars (0 to 5 years old): 65% RH
Old cigars, i.e. cigars I bought when over 5 years old, or cigars I plan to age long term: 60% RH
Very old cigars, a few decades old when purchased: 55% RH
Note for the RHs and Temps in °F, the figure are always round to 5s. Because no matter how good your storage facility is. It fluctuates. It runs on a thermostat mechanism, the temp and RH are never static, when the temp is cold enough, the cooling mechanism stops, when the temp rises to a certain level, it triggers the thermostat and the cooling mechanism is turned on. It is quite like when doctors measures blood pressures it’s always in units of 5 , like 125/85 etc. Why? Blood pressure fluctuates. This minute you measure it, no matter how accurate your measuring device is, it may be 127.312/84.404, the next minute you measure it, it becomes 124.274/86.692.
For practical purpose for everyone.
I think 65°RH and 65°F (~ 18°C) should be fine.
Interesting note:
65°F = ~ 18°C. Comfortable room temperature is ~ 24 – 25 °C, which is ~75°F to 77°F, which means all expensive humidors without temp control are totally lame for storing cigars, even if you buy the 70/70 bullshit. 70°F is ~21°C, which is way too cool for any comfortable room temperature. A fact they didn’t tell you when selling you those US$2,000 humidors with exquisite wood inlay.