If I had to wager a guess as to what the issue stems from, I'd argue that the models have recently been toyed with as to allow for higher snowfall accumulations through moist-saturated near-sfc columns. This error seems to show up almost exclusively in the immediate vicinity of the coast, exactly where you'd find enhanced lift via the sudden onset of terrain, and the most saturated lower troposphere, right from Pacific onshore winds in a lightly unstable environment.
Wouldn't doubt it would be a useful tweak given recent marginal snowfall busts in the Northeast, but since the greater Northwest sits in a gradual transition between a subarctic and subtropical maritime climate zone, where snow can fringe on the hair of dewpoints and Chris' 925mb temp maps and how badly you pray at night, subtle tweaks can wreak havoc on our beloved #snowmaps, as pretty as the colors may be nowadays....
35F and raining here. The upper levels have warmed now. I was down in Victoria earlier this evening and there was some sticking snow around the south end of the Lake. It was all rain on my way home though.
I think I'll drop dead from shock if the ICON ever has a run that shows actual lowland snow. That is the most stingy azzz model I've ever seen. Never showed anything in the areas that actually got snow last night either.