I agree with Alex and Clearwater. I live in WY where the relative humitiy ranges from 5% - 70% but not in the same season. In the winter here, there may be 2 feet of snow on the ground but it is dry enough to sneeze and get a nose bleed. That or you walk across the room and you are able to arc weld with the static electricity that you generate (ok a bit of a stretch, but...).
Seriously the climate is dry enough out here when it is cold, I have to humidify my house. Mold could be a problem in the spring / summer but not usually.
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A government big enough to give you everything you want,
is strong enough to take everything you have.
Thomas Jefferson