I doubt anyone has the answer to your question and it involves so many variables. Rather than dealing with all of those variables, most provide adequate ventilation to allow the bees to deal with it. Depending on your climate, some add "quilt boards/boxes" to help reduce moisture during wintering. J
I use reduced upper and lower entrances and have become a huge fan of quilt boxes. Quilt boxes exploit dew points to remove moisture from the bee space. I use them on all 7 of my colonies, so far 100% winter survival going into my fourth season. If you'd like an explanation of why they work so well in the north just ask, I'll be happy to explain it.
I use quilt boxes, too, and also don't like to winter without one on each colony. I often keep them on the hive all year round.
Something that I did differently this year (mostly out of sloth, at least so far - now I am just curious) is to NOT open any vent holes above - or in the sides of - the quilt box. I would have predicted I'd have a soggy mess, but that has not happened. I am watching closely now that spring is here because traditionally I saw much more vapor escaping from the vents in the spring than during the winter. The vents are in place, just covered with plastic plugs, so I can open them if it becomes a problem. My QBs are shallows with a cotton fabric floor, filled heaping full of pine shavings. I have 1.5 inches of foam above them in the telecover. No inner cover at all. The upper layers of the shavings are dampish, but only in the corners. The shavings below are dry. The inner surfaces of the vent shim above the QB are wet, but not moldy. (Probably still too cold for mold.) One of my concerns about QBs was whether they were too effective at removing moisture from the hive. I am quite surprised by how things have turned out.
The temperature that condensation forms at is dependent on a lot of variables. In general at above 95% RH you are going to start seeing condensation. The water "capacity" of air depends on the temperature and pressure. RH (Relative Humidity) is a measurement of the amount of water in the air relative to what it can hold. Typically you will not get condensation during the day (because it is warm), but you get the condensation at night when it is cold.
At a high level the reason you see condensation/frost on grass/windshields/ect in the morning is it gets cold overnight and the temperature of surfaces drops colder than ambient air (due to radiation to cold temperatures in space). The air comes in contact with these cold surfaces and can not hold the water it has so the water condenses out on the surfaces.
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