I have been studying the latest computer forecasts and it is clear that this weekend will bring major changes....but no snow in Seattle.
Starting with today, low clouds and the inversion are still in place over Puget Sound and eastern Washington (see satellite picture and the latest profiler temperatures in Seattle). The inversion is a weaker than last week on the west side...and some locations are seeing some sun midday. But the clouds fill back in overnight. And tomorrow won't be very different.
I have added a figure showing temperatures over the past four weeks against the average highs and lows (red and blue lines). During the last week we have been much cooler than normal..which comes as no surprise. The spike of really warm temperature two weeks ago was the pineapple express flooding period.
Now to the forecast. An intense high, associated with very cold air, will form over the Yukon and N. British Columbia and move southward towards our region. By tomorrow morning at 4 am, a 1054 mb high will be over northern BC. (see figure), and cool air will begin seeping into northern Washington. By saturday cool air will be moving SE in the Fraser River Valley and NE winds will be hitting Bellingham and NW Washington (see figure). Colder air will move southward on Sunday, but right now the models indicate very little precipitation....so no snow. Moderated arctic air will move over western Washington and we will probably clear out on Sunday. With dry conditions and offshore flow the strong inversion and fog that we have experienced should be history.