hi
I have a two storey house in houston texas. This friday we got about
3 inches of rain at around noon. I was in my master on the second
floor for the good part of the rain.
When i went to my first floor family room I noticed water on my
couch. I looked up to see a water stain from my vent. I quickly
opened the vent to find it was completely dry and concluded that water
was just using the opening to drip down. Now the rain although not
heavy was steady by the drip had stop.
I went up to the second storey and noticed no leaks in the ceiling
just above. I also went thru the attic with a flood light and
although the space is tight could not find any water marks by the
drain vents etc.
So i am lost as to how water was dripping thru the first floor with no
evidence of it on the second.
Now to the left of the family room is the guest bathroom which has
it's drain vent and plumbing pretty far from the drip. I cannot
imagine any plumbing in the area of the drip. The guest bathroom does
have an exhaust which is about 3 feet from the drip spot.
All the drain vents on the roof were re sealed after hurriance ike.
And i should mention that during hurriance ike we did have a drip spot
about a foot to the left of the new one.

So my quesiton is where do i look and what do you think is going on.
The drip spot is about 9 feet from the shingled house side. Where
could this drip be coming from. It also rained all day today pretty
heavy and the drip is gone.

If it was the plumbing or the drain it would be consistent but it
isn't.
Please advice and thanks for reading.