Everything is proceeding according to the weather plan this evening. The well-advertised cold airmass is moving in. I’m just amazed at how cold it is here in the 2nd half of April at 10pm. Our tower temp at 1800′ is 30 degrees, a dusting of snow has fallen in spots at the Coastline, and it’s only 16 degrees at Timberline!
The core of the upper-level low is currently over Southern British Columbia, and only moves to S.Central Washington by Monday morning. I have scanned lots of maps and see little to no organized areas of precipitation through Sunday. That’s the main reason I’ve laid off the possibility of snow in the lowest elevations here in the Western Valleys. It’s clearly going to be cold enough the next 3 nights for snow to stick down here, but the moisture seems to be limited to mainly afternoon/evenings inland. The Coast is a different story. Pretty much a constant feed of heavy showers move onshore now through Sunday. So at night some accumulation is likely even at the lowest elevations out there.
What happened in Seattle tonight really shows what precipitation intensity will do in this airmass. 3-5" of snow in N. Seattle/Everett, while it was 40 degrees or higher in the central/southern part with little or no precipitation. So I’m VERY aware that any organized area of showers could give us a "surprise" snowfall here in the metro area the next 2 days. I’m crossing my fingers and assuming that won’t happen. Enjoy the weekend and discuss amongst yourselves…maybe we’ll hit 85 just 10 days from now??? One can hope…Mark Nelsen