No!…The Dreaded Split Flow!

November 18, 2008

Junk I don't usually post this early, but I'm sitting here with all 3 weather graphics computers down while doing an upgrade.  So I had to share this image.  Click on it to get the full deal.  It's the 12z GFS at 144 hours, next Monday morning.  It shows a "perfect" split flow pattern on the way.  The previous model run didn't show it quite so strongly, but I see the 12z ECMWF is quite similar.  Bad news for skiers/snowboarders.  If this verifies, along with the maps that go out to 10 days, the ski season is going to have to wait until after the Thanksgiving Weekend.  There are worse weather patterns than a big ridge in winter in my opinion.  This would be it.  I also realized that we never once saw this pattern last winter.  Doesn't mean anything for this winter, but shows how consolidated and chilly last winter's pattern was.  More later…

Okay, it's 10:00pm and we just finished hootin', hollerin' and clapping at the beginning of the show (you don't hear that, we stop just before the anchors begin).  So here's a quick update.  00z GFS and Canadian show either ridging or split-flow through the first of December.  Quite a turnaround from the wet start to the month. 

In the short term, I did some quick touch-up surgery to the metro and Gorge forecasts for tomorrow.  Gradient PDX-DLS is switching around quickly to easterly and our RPM shows 6-7 millibars by midday tomorrow.  That should produce wind gusts to 50 mph at the west end of the Gorge and 35 mph at TTD, Gresham, Camas etc…  That will finally clear out the low-level muck for most of us though.

No other deep thoughts for this evening; I think I exhausted my brain cells on those life-altering thoughts in last night's post…Mark Nelsen