Snow is Coming Today to Western Washington, But Not Too Much for Most

I am going to go against one of the rules of the click-baiting online world.  I am not going to even hint there is going to be a big snowstorm over Puget Sound land.  Yes, most of you will see some flakes, but for most the ground will be barely whitened.

As we shall see, a highly transient Arctic Front/convergence zone will bring a few hours of snow showers, with totals ranging from a few tenths of an inch near the Sound to perhaps 1-2 inches in the far eastern suburbs.

I am going to show you some forecast snow totals....but keep in mind there is lot of uncertainty regarding the exact distribution of snowfall.

The latest super-high resolution (1.3 km grid spacing) UW WRF forecast (below) for 24-h snowfall (through 4 AM Monday), shows light snow ( 1 inch( over NW Washington, with 2-4 inches over the northeast Olympic Peninsula. Most of Seattle is around 1 inch, with some heavier snow east of the city.  LOTS of snow in the Cascades.


But you should NEVER depend on one forecast in such situations.  The UW high-resolution ensemble forecasts, with many forecasts, shows that at SeaTac there is a lot of uncertainty, with the best estimate (the ensemble average) about .7 inches.


Over north Seattle near Magnuson Park, the average forecast is about an inch

And near Lake Sammamish and Issaquah, nearly 2 inches--but again lots of uncertainty.

The temperature forecast remains the same: huge cool down tonight (see plot below).

The National Weather Service has pulled back a bit on snow totals, now going trace to 1-2 inches around Seattle.  Enough snow to enjoy, but not enough to cripple the region.  Most of the snow will fall before 10 PM, so SDOT and WSDOT has the overnight hours to prepare for the commute.


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