Some great answers here, especially from u/insom187:

https://www.reddit.com/r/Washington/comments/yfzdna/comment/iu6z7ac/

The rainy season has finally returned to the Pacific Northwest so be sure to bring rain gear. Remember to dress in layers so you can adjust as you warm up.

To the list in the answer above, I would add that all of this stuff is great in the cold, damp, and gray season.

• The Hoh Rain Forest is meant to be seen in the gloom. It looks...not right...in the sun.
• The lodge at Lake Crescent has benches and chairs you can use to admire the view. If the restaurant is open, it's quite good (though pricey). Definitely do the short hikes.
• You should also stop by Hurricane Ridge, uphill from Port Angeles. It's a beautiful alpine meadow and there are some nice hikes there too. Even if it's wet.
• Rialto Beach is across the river mouth from La Push. I've been there during a storm. It was impressive seeing the tree trunks on the beach tossed around like matchsticks.
• In Forks, Sully's Drive-In is great. Takes you back 50 years except for the prices. Pacific Pizza is surprisingly good too.
• The Quileute Oceanside Resort & RV Park at La Push (https://quileuteoceanside.com/) is great. Like everything in the Forks area there isn't much there, just the ocean and the surf. But that's why you go there. Some rooms have covered balconies so you can watch the ocean and surf during wet weather without getting wet yourself.
• The beach scenes in the first Twilight movie were filmed at Cannon Beach, OR, and Indian Beach, which is a little bit north. You won't recognize anything except in a generic PNW way.
• The Italian restaurant from the book (Bella Italia, in Port Angeles) is worth a visit, but again you won't recognize it. The scene was filmed in St Helens OR IIRC. They have a dish modeled after whatever the mopey girl had on her first date with the sparkly guy. I haven't been there since the pandemic started but have heard that it's still good.

Also, if you walk on the beaches, CHECK THE TIDE TABLES. Other people have said this but it bears repeating.