Where do full timers go out west to escape the heat?

As mentioned, the PNWet, far north CA, OR, WA and ID. If you're going to try and stay on the coast, be prepared to be turned away without reservations, so get them if you can. Also on the PNW coast, be prepared for wind, overcast and cold even during the summer... but it can be beautiful.

Although not necessarily escaping the heat, if you're in OR, make sure and spend some time near John Day, go to the Painted Hills NPs.