PatrickC is correct. Distance, and the necessity of planning in advance, does make it harder.
It's even more complicated than what I said. Based on the streams themselves. For instance, maybe on one stream, the fish go way upstream quickly. On another, there maybe a waterfall or something that prevents numbers from passing, except in SUPER high water, so you wanna be below that falls if there hasn't been a recent flood. In winter, maybe one stream gets blocked up with ice, preventing fish passage, while another stays open.
I recognize this is all hard to know, and impossible to plan for. So it's rather daunting for a beginner. Just know that steelhead fishing is typically either on, or off. When it's on there's nothing like it. But driving all that way for a skunking or 1 or 2 fish in a shoulder to shoulder crowd is a distinct possibility.
But if you can't decide last minute when to go, schedule the trip well in advance. If given a choice of times, I'd pick November. Buck season would be perfect if you're not a hunter. If you are, a 1-5 weeks earlier is fine (later can get tricky with weather and ice). Get your hotel, etc. Just don't lock yourself into a spot. Print out the maps from fisherie.com. I concur about Nagy's steelhead guide, excellent book. Get yourself learned up a bit.
Watch the radars in the days prior to your trip. Call a shop on the way up. Pick your spot when you get there. If it's lower than you'd like, and you see fish but they have lockjaw, MOVE. If it's a bit on the high side, and you can't see fish in most spots, perfect. Start fishing likely looking water. They're trout, and hang out where trout would. When you start hooking up, sit on that spot a while.
Other advice: try to stay away from the immediate mouths, especially on the more popular streams. Fishing may be fine but super crowds are not. You can find places that are merely "crowded" by other standards, but not opening day type crowded. If you find a big, slow pool with a bunch of visible fish in the bottom, go ahead and drift a nymph through. If the pod of fish parts like the red sea, don't waste your time, keep walking. Those fish aren't active. I know how hard that is when there's 50 24 inch footballs laying there. In the head or tail of the same pool, there may be a smaller number of more active fish. They're the ones you can get. But they are likely to be less visible.