Forecasters say Western Washington will get up to five inches of snow in some areas Friday morning before it turns to rain.
A Winter Weather Advisory is in effect Friday morning from 1 a.m. to 10 a.m.
University of Washington Atmospheric Sciences Professor Cliff Mass says the snow likely won't let up until 8 or 9 a.m. so the morning commute will likely be a white one.
"The bottom line is clear: the commute time on Friday morning will be a white one, so be prepared," Mass writes in his weather blog.
The Seattle Department of Transportation said Thursday afternoon it is prepared for snow and "pre-treated snow routes."
The National Weather Service forecasts 1 to 5 inches of snow from Tacoma north. Forecasters also expect 1 to 3 inches on the coast and southwest Washington.
Exactly how much snow each area will get is hard to predict, but Mass offered some estimates.
"Over the city, it looks like we're talking about one or two inches. You go to the Eastside, start moving into Bellevue and then to Sammamish, you maybe get 2,3, 4 inches. You go north to Everett, and then further north, maybe 3 or 4 inches. And the mountains we're talking about a foot. They'll be getting some real snow up there."
Heavier snow is expected in the mountains, making driving difficult through the Cascade passes. And snow is forecast in southeast Washington. The chance of rain or snow will persist through the weekend in Eastern Washington.
Forecasters expect drier but cloudy weather through Christmas in Washington.
Return to MyNorthwest.com for school closure and delay information.
The Associated Press contributed to this report.
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