The National Weather Service in Seattle has issued a Winter Storm Watch for Thursday morning through Friday morning.
According to the advisory, a weather system will move over western Washington on Thursday and Thursday night bring precipitation. Cold air will already be in place making it likely the precipitation will begin falling as snow before changing to rain.
Around 12 hours of snowfall is possible at most locations in the interior lowlands and four inches or more of snow is possible during that time.
The onset of snow and the subsequent change to rain will happen first in the south part of the state as this system will move south to north. By Friday morning it is anticipated the snow will have changed to rain everywhere.