An organized band of rain and snow is expected to move in to the Puget Sound area from the south Saturday night.
Forecasts show a couple hour window of a mix of rain and snow. It should arrive along the coast late Saturday afternoon, shift over the south Sound around sundown, pass Seattle near or just before midnight, and move up into the North Interior pre-dawn Sunday.
This band is going to give more widespread (but light) accumulations. About 1-2" are expected for hillsides above 300 feet in elevation. We may see a few wet flakes down to sea level, but any accumulation should be negligible, and main roadways should just remain wet.
Even those who see snow accumulate will likely see it melt within a few hours.
There may be a few more lingering snow showers early in the day Sunday, but with temperatures warming in the afternoon, the snow level will rise, and the snow chances will turn mostly to rain showers.
For Sunday night into Monday, forecast models are hinting at another convergence zone developing along the King/Snohomish County line, leaning a little closer to the Hwy. 2 corridor. Those areas could get hit with some more localized accumulating snowfall for Monday morning's commute.