My most recent half marathon was the FT Flat last July; it just wasn't a good day for me, and I went over three hours, when I thought I could avoid doing that ever again, after my first half marathon (when I was just proud to have finished, regardless of time).
Before that, it was a full year back to the FT Flat the prior year, where I set my current official half PR. Though in between I ran my one and only marathon, during which I ran the first half faster than that half PR! Note: that's not a very good pacing strategy for a full marathon.
This training cycle, I started out pretty strong, but between getting lazy, some work stress, and colder-than-normal weather, that eventually petered out and I hardly did any speed training the past month, and only got up to 10 miles for my long run (though, did do that twice!).
So, I'm not sure how overly ambitious these goals might be.
A goal: 2:42:53 (12:26) - beat my unofficial PR
B goal: 2:48:42 (12:57) - beat official PR
C goal: 2:59:59 (13:43) - beat three hours
Fortunately, the weather is about as good as could be hoped for on the western side of WA or OR during the last weekend of November - very cold, probably right around 30 degrees during the race - but DRY and sunny!
The last time I ran a late fall or winter race was the Holiday Half in Portland, which is in mid-December, a couple years ago, when it was not just cold (35 - 40, I think), but also very rainy, and very windy. It was quite a miserable experience. And that's the main reason I picked the Seattle Half when I decided I wanted another longer race for the year, hoping that those couple weeks earlier in the year would keep the weather from being quite so nasty!
So I expect to be quite chilly before the race (but I'm staying at a motel just a quarter mile away from the start, so I can delay my arrival pretty late, without worrying about parking), but otherwise my biggest concern will be the hills. There are supposed to be some flat sections, but also a lot of hilly parts. (I've looked at the course map, just not familiar enough with Seattle for it to register what the terrain what will actually be like.)
Mostly, I'm hoping to run well enough to not be miserable, and remember that I actually do enjoy running and am doing this voluntarily. :)