Silly story, perhaps an electrician can give me some insight.

I have an outside electrical box that I use for Christmas lights. That outlet is tied to a GFCI outlet in my garage; seemingly, at even a minor amount of rain, that GFCI will reset - and that becomes a problem for Christmas lights LOL.

The odd thing I remember is that my last house, built by the same builder (whom I'm going to guess used the same electrical sub, but don't know this for a fact), had precisely the same problem on an external plug, but the GFCI that one would trip was in my master bathroom.

I finally got irritated enough by the problem to call an electrician and have them come out and fix it, and the guy asked me who did the house wiring, and I didn't know; but he did offer that the "wiring on the GFCI was really weird," and he explained why - but that was 20+ years ago and the explanation escapes me. So I'm assuming it was probably the same electrician (and I DO remember the electrician on this house being an insufferable jerk) who did something equally weird, but I don't know what.

Any ideas? Would surely like to get the thing fixed.

I'm not an electrician, but I do know that some GFCI's can be very sensitive. Codes require them in wet areas and on outdoor outlets . And in shop or garage areas, they are supposed to be on the first outlets on each circuit coming off the panel.

I don't think i've ever not heard an electrician gripe about another electricians work when having to go behind them, no matter how old the work is. Your situation may have to do with how the previous electrician tied the circuits together, which was probably acceptable at the time, but may not pass code today.

If it were me, i would either replace the old GFCI outlet with a new one, or dump it all together for a standard outlet.

I am an electrician. Sounds like the GFCI outlet might be a bit on the sensitive side but it is doing what it supposed to do. It's seeing a ground fault caused by moister creating a connection between the "hot" leg and the ground or "neutral" legs. When things dry out all should be fine.

When it all dries out, put a bubble cover on it if it doesn't have one. They are designed to keep the outlet dry while something is plugged into it, like christmas lights. Old style flip covers aren't. Make sure water cant get between the back of the cover into the outlet too, either with the gasket that comes with it, silicone or both.