One thing you should be aware of, Oregon and Washington have some very nice places to visit. So, A really large herd of Rvers both local and those coming from afar are gobbling up reservations.
Example: It took me two years to get a reservation into Silver Falls National Park. I had the site picked out that I wanted and soon as the reservation desk opened I was trying to get in. The first year, not knowing any better I just drove up to the gate and asked if they had any openings. The guard said yes, in the over flow parking area. We went some place else that year.
So, pick out where you want to go then have a couple of back up sites also picked out.
07 Jayco Eagle 288RLS