FWIW the CFS has been more consistent with the cold January, but December shows up good at times. I think we will at least get something in December even if it's just a brief cold shot with a dab of snow.
Prune Hill does fine when there's relatively weak outflow. Example being 2/9/2019 when they were one of the big winners in the region with about 7-8". With stronger gap outflow events and events that have more of a downslope/mountain wave component, they can get skunked a little bit, I think in February 2014 their accumulations were about half of what Ridgefield and Salmon Creek got. But overall I think it roughly balances out on the whole with some of the other good areas around the county.
The same is true for the areas north of Washougal. Up there to the south and east of the Washougal River there's a lot of big lots around 700-800'. Still fairly gorge-y, so you still get a lot more ice up there than a little further north in the county gets. Also still a fairly easy drive into Washougal.
I think the highest homes in Clark County are generally around 1400-1500' up around Rawson Road and then there are some areas off of the Little Washougal River around 1400' as well. The areas near Rawson are fairly accessible from Hockinson/Orchards and are generally out of the gap winds unless it's a mountain wave. But they also can get warm-nosed in some shallower outflow events as a result.
Any of these areas also do fairly well with onshore flow, especially any places a little further north that are less exposed to southerly flow (Prune Hill is probably the most exposed of any of these areas).
Prune Hill is a really nice neighborhood though, so depending on your ideal work/home situation, it can be a really good fit in a lot of cases. Like others have said, the 350 days without snow have to weigh the most heavy!