I found this nifty (and much improved) page on the Army Corps of Engineers – Portland District webpage while chewing through my salad and meatballs for lunch. You can click on the image to get a closer look. It’s pretty obvious that there is a LOT of storage capacity in the Willamette Basin right now. Reservoirs are nearly empty in anticipation of either a flooding event, or more likely, lots of spring snowmelt. I sure see no sign of any warm/rainy event that would last several days. You can go to this link to find the same map, but a bit more interactive: Willamette Reservoir Info
Short term weather shows another Pacific frontal system approaching the Northwest. The atmosphere overhead warms significantly overnight. Combine that with cloud cover and temps should stay right near 40 degrees. Just ahead of the cold front tomorrow afternoon, the freezing level rises up to 5,000′ or so. It seems so excessively high, but that’s because we’ve had 3 weeks of very low freezing levels. Behind the front the 850mb temps drop to -5 or -6 tomorrow night and early Wednesday morning. Early in the winter we’d be all excited about snow to the hills, but obviously we’re all getting numb to that kind of talk now. That’s pretty clear by the lack of comments on the previous post…is everyone worn out? Waiting for the daffodils to come pushing up and the first 60 degree mostly sunny day??? Could be. But don’t fret. I see the ENSO Diagnostic discussion hints that La Nina may continue into next fall…hmmm…another La Nina winter? I’m sure we can discuss that in GREAT detail next summer right?
Another "warm" system comes through Thursday, followed by weak ridging over the weekend. The ECWMF was mostly dry with very warm 850mb. temps…from +2 to +5. The 12/18z GFS was significantly cooler with just the usual up/down freezing levels. No one storm from Friday-Tuesday looks all that interesting to me. Not compared to what we’ve seen THIS winter. No sign of lowland snow OR a big freeze in the next 10 days, which just about takes us out of the period when we can see a prolonged cold event. BUT, La Nina winters have often been followed by cool/wet starts to spring. I remember 4" of snow at 800′ elevation in mid March in 1999 (I think), and even 2" at that elevation around the 3rd of April. So those of you in the hills have the possiblity of snowfall for the next 6-8 weeks! Down here in the city, we know from just a couple year ago that snow can fall in the city through the first week of March…Mark Nelsen