A Chilly, Crisp, & Windy Christmas

December 24, 2009

I’m really tired of staring at that radar dome each time I check out the blog, so here’s something fresh.  I’ll be working again Christmas afternoon/evening after a nice 8 day break.  So the biggest question I have is: what lies at the foot of the statue?  Anyone with any insights on that can let me know.  I’m “Losted” out after watching the whole season in about 5 days.  So let’s move on to weather.  Three items of note:

1.  East wind is going to begin raging tonight and continue through the weekend…strongest tomorrow night and Saturday morning.  Gradient is up to 6 millibars at 1pm, giving gusts over 50 mph now at Rooster Rock and Corbett sensors.  A gradient of 10-12+ millibars is likely by tomorrow as much warmer air continues moving in overhead over and west of the Cascades, capping a cold airmass moving westward.  This setup with 850mb temps up to +8 overhead really “squeezes” the flow through the Gorge.  Add to that an approaching surface low from the southwest tomorrow night/Saturday and we get very strong wind gusts, probably 65-70mph at the west end of the Gorge and 40-50 mph Troutdale/Gresham areas.  Not a damaging event like last January…we had 850mb temps up around +17 then!  Maybe a Saturday midday Vista House meeting???

2. Freezing Rain Saturday night in the Gorge and maybe far eastern suburbs too?IF we get moisture up here, it’ll be cold enough for freezing rain, but that’s a big IF.  Most likely it’ll stay dry.  See item #3

3. El Nino dry and mild conditions continue until further notice.Has anyone noticed that we’ve seen no real westerly flow with a good Pacific Jet since Thanksgiving Day?  We’ve either had split flow over the East Pacific/Western USA, ridging right over us, or ridging just to our west (cold spell) for most of the time.  And models show the same into the first week of the New Year.  Very pathetic looking if you want active weather.  Both the GFS and ECMWF show another possible warm rain episode for the mountains around 8-10 days from now.

Merry Christmas!

Chief Meteorologist Mark Nelsen