Originally Posted by
Billy Stephens
A quick google of Average Relative Humidity shows a yearly average of the 6 PA cities listed of Allentown 56%, Erie 66% and Oct,Nov,Dec in the 70% range 50 to 65% does not sound unduly high.
That is RH of outside air. As the outside temp drops teh airs ability to hold moisture decreases. As the air is brought inside and is heated it's RH goes down. 50-60% indoor Relative Humidity would be quite high in the winter.
example:
If the outside air temperature in winter is 0°F and the relative humidity is 75 percent, that same air inside your 70°F home will have a four percent relative humidity. That’s dry! The Sahara Desert has an average relative humidity of 25 percent.
Humidity and the Indoor Environment