Sandy, I'm not sure that you're overtrained as much as under rested. At the moment I have about 500 km under my wheels since Jan 1. I've been out in the rain several times but try not to ride in the rain because the only place around here without cars is the hills and riding downhill on slippery roads isn't all that much fun.
If I were you I'd take a week of very moderate riding and get plenty of rest.
