We had this issue and the flapper on the outside of the vent had gotten clogged with lint and was stuck open (so it was condensation from outside air).

Check the vent. It may have gotten rain in it in the thunderstorms.

OP...yes, I'm serious. I'm 40 and have been doing my laundry since I was 10. I can't recall our dryer ever having visible moisture on the inside after not being used for two days.

Are you serious right now?

If you're throwing in wet clothes why do you need to wipe the dryer out? It's going to get wet again.

I recently noticed that our dryer seems to be producing quite a bit of condensation inside. I just went to toss a load in and actually had to wipe down the inside of the dryer's drum. Our laundry room is on the 2nd floor with the bedrooms and vents to the side of the house. I'm not sure if it being higher up in this heat has anything to do with it. At any rate, is this normal? How can this be prevented?