I seem to remember this topic coming up before but I didn't pay enough attention to it because I thought it didn't concern me. Now it does! On my recent Utah trip, we had some nights in the uppe...
I was one who posted on this recently, after getting "rained on" one night (it was raining and we had closed up the vent, and my first thought was that my vent was leaking, it was so bad) - and heeding the replies of this forum, the problem was solved by opening the ceiling vent a bit, and cracking open a couple of windows.