Fence boards warped

I just put in a cedar fence this summer. I put the cedar boards next to each other with no gap. I was trying to achieve a privacy fence with as little of a gap as possible. I knew when the boards dried out there would be a little gap. I also put two coats of sealer on (water based). The boards were never cut so the ends were still sealed. I was told that when you get the wood they at their saturation point and they will only shrink from there. Well that was all well and good. The boards dried out in August and September and a gap of 1/8" to a 1/4" was seen. We have had above average amounts of the rain in the last couple of months. I live in Portland Oregon so to be above average here is saying something. Now the boards have swelled so much that have twisted and bowed. I doubt when the boards shrink in the summer they will ever be the same. There is about 350' of fence. The part of the fence that got the afternoon sunlight in the summer has not twisted or bowed but the other 280' has. If I end up replacing the boards I am looking at about $1200-$1500 and not to mention the labor. Any suggestions would be appreciated on what went wrong and what I can do to fix the situation

Thank you
Tim

The boards have probably buckled from pushing sideways against each other. If you merely replace them, using your original scheme of tight together, the problem will likely re-occur. If you don't put them tight together, you won't fully satisfy your privacy objective.

You didn't state whether the boards are vertical or horizontal, but either way, you might consider adding purlins (?) across the joints and screwing the boards to them. Note screws, not nails. This should pull the boards into alignment. Try this at a test location before committing to purchasing all the new material. As to appearance, arrange them to create a new design feature instead of a ham-handed fix.

Another option, of course, is to wait until summer and see if they recover satisfactorily. In that event, it might be wiser to learn to love them when they're wet and buckled.

Joe