I had a GFCI breaker that would do that. First it was only during
thunderstorms. After awhile it started tripping out if the humidity
got too high. Of course, I was not sure if it was tripping for a good
reason. Finally decided to replace it and see what happened. The new
breaker has not tripped so far.

Gary Dyrkacz

Radio Control Aircraft/Paintball Physics/Paintball for 40+
http://home.attbi.com/~dyrgcmn/