My spot is way the fuck closer, and not in Eastern Wa at all.
Again, still posting from a phone, so no Google fancyness, but the campground of which I speak is within [shitty] walking distance of Elbe, WA. It's more or less on the back side of Alder lake. Pleasant Valley Road, off SR 7, near Mineral Road.
I submit a comparison between weather reports:
Naches, Wa: 91-95f Fri-Sun
Elbe, Wa: 75-85 Fri-Sun
I'm leaving Vancouver now, I'll reconnoiter the site on my way home tonight.