Although I'm guessing the risk of arctic air is much lower to negligible in Chile/Argentina...mostly maritime polar airmasses.
Anyway, for anyone interested, I made a quick spreadsheet of the climate from both locations, but I matched the seasonal months with each other for each location.
The primary differences between the two are that Osorno is a bit wetter than Portland and Portland is quite a bit warmer in summer (I thought they would match up better than this, but the summer had a greater difference than I thought). They do match up somewhat well though (at least pattern wise), considering they are 6700 miles apart and in opposite hemispheres.
If Portland was nearer to the coast or if Osorno was a little bit more inland, they would probably match up better. Still, they do bear similarities to each other, climate wise.
If one were to look at several locations in the Lake District as well as several locations in the Pacific Northwest, I would bet that you could find some pretty good matches.
You could find some pretty good matches scenery wise too.
Just for fun.....
Mount Thielson Oregon:
Cerro Puntiagudo Chile:
Mount Hood Oregon:
Volcan Lanin Chile:
Mount Bachelor Oregon:
Diablo Lake Washington:
I think Bordeaux is closer to Portland than Orsono.
It looks like you are right. I was thinking Chile since I have been there, but not France.