@Front Ranger Some of our wettest Novembers on record have been mild and ridgy. Which is a minor adjustment away from being chilly at sea level with ridging overhead, and very dry. You can not tell me with a straight face that precip alone is a reliable climactic indicator when its response to any given pattern is so sensitive to minor adjustments. It is too random.
That just isn't true, especially after mid October. Seattle can get multiple inches of rain in a day while heights are above normal and a trough is centered offshore pumping AR moisture into the region.
It's averages over a long period of time. Like any other long term average, there is no one answer - many different types of patterns, etc contribute.
But in general, more troughing is the answer for more precip when looking at that kind of sample size. It's not uber complicated.