@Benji @JonKramer Yes, that is the natural humidity if you live in a wind tunnel. At the minimum have a steamer on at night, or you are a covid magnet. We, in Canada, usually have sealed windows. In fact, the new super houses need an energy air exchanger to stop the windows from raining.
@hasmis @JonKramer that’s also natural when it’s cold outside and warm inside. The vapor pressure vs temperature shows that , if you keep vapor pressure (moisture content) constant and increase temp, the relative humidity (relative to the curve that separates liquid water / vapor) drops. So the air is always drier indoors in wintertime, unless you sealed your windows and are able to increase moisture content artificially (humidifier, shower etc ). No need to be in a “wind channel” 
