Why is water leaking into my service panel through conduit from below?

The leak is in our electrical box. The water comes out in drips from the main conduit which ultimately goes out to the street. I have confirmed that the water is coming out of the conduit from the inside.

The main leaking conduit goes up from the fuse box, which is inside our house, and up into the attic. The conduit makes a sharp turn and goes about 20 feet to the edge of the house and goes down into the wall. I presume it then hooks up to the meter. I presume the meter then goes directly up through the attic again to the stem-thing that dangles the power to the street.

There are no leaks in the roof. If the conduit goes up, then travels in a dry environment, then goes down, how could water physically be getting in there? The conduit is bone dry. I've crawled the length of it and see no sign of moisture. The dripping has been monitored for about a week. It sometimes drips when it's raining, sometimes it drips when it isn't raining, sometimes it doesn't drip at all. It's madness.

I've inspected the roof for leaks. None. There was some flashing on the roof near the Fuse Box that was on the outside of the shingles, which is obviously bad. But I didn't see any evidence of leaking near the spot in the attic. I tarred it up regardless. But the leak came back the next day and has been going strong for a week.

Also worth noting, the meter is bone dry.

Also, how it was discovered: A breaker blew about a week ago. We discovered about 5 ounces of water pooled up at the bottom of the fuse box. There was also water, which dripped down from the conduit, dripped over the fuses directly under the trajectory of the conduit opening above, hence the blown fuse. Only one blew.

Over the week of it being monitored, about 1 - 3 table spoons of water have been dripping from the main conduit every day.

I'm in Portland, OR, so it's very wet here. I've lived in this house for over 10 years, no issues until now.

Here's a crude illustration:



And it gets worse. There is a smaller conduit that when going up in the attic from the fuse box snakes in the other direction of the main conduit. It powers the Washer/ Dryer, so I presume it goes down the wall and goes to the Dryer. It is leaking from the inside as well.

The 2 leaking conduits do not cross paths and seem to be 2 completely different issues.

I have some videos here. Maybe one of you are seeing what we are not. NOTE: I imagine I swear in these videos, so, ya know, beware.

I suspect condensation. If you're in a climate like mine, warm air is rising in the conduit, where it cools and the vapor condenses on the pipe. Even though the pipe drops down to the meter panel, it ultimately vents higher than the interior port, which results in "chimney effect". A breeze across the masthead would also move air out, as could positive interior pressure.

Plug the pipe with duct seal (purpose-made putty) in the panel, but leave a tiny drain hole so you can monitor moisture. This should block airflow enough to stop most condensation. See what happens over a few days.