The National Weather Service has a constantly updated snow total map (see below) that shows how variable the snow was. Around 2 inches on Bainbridge and near Tacoma, but 2-5 inches in Seattle (I had 4 inches in northeast Seattle). But amounts increased to the east and north, with around 6 inches in Bellevue and Everett, and even more near the Cascade foothills.
The UW forecast model for the critical 24-h period (4 PM Sunday to 4 PM Monday) made Sunday morning only showed 1-2 inches over Seattle and Everett.
The forecast starting 12-h later (4 PM Sunday) was much better, but that was only available a few hours before most of the snow fell.
The ensemble forecasts yesterday were going for snow, but suggested that the most probable value was around 2 inches. So our forecast systems clearly underplayed the amounts...particularly in the days before.
But this forecast was not an easy one (dependent on the existence of hard to forecast snow bands rather than larger-scale fronts), so I would argue it was fairly successful...particularly since the temperature and winds were fairly well predicted. Much better than we could have done a decade before.
The roads are a mess though--even major ones like 405 and its on-off ramps. Did the SDOT and WSDOT pre-treat the roads last night with deicer solutions? I didn't see such activity last night driving around, but I could have missed them. But pre-treatment is REALLY important in this kind of situation, starting with warm roads followed by a major chill-down.
We have some dry days ahead, but a another, possibly larger, snow event is predicted for Thursday/Friday. For example, bellow is the 24hr snowfall forecast ending 4 AM Friday. Huge amounts on the east side of Puget Sound, with 4 inches extending to Seattle. Too soon to be sure about this one, but keep it in mind.
from Cliff Mass Weather and Climate Blog http://bit.ly/2RDz1Jm
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