Tired of the rainy season yet?
Before IÂ talk about La Nina winter weather for Portland, Seattle and other northwest places based on the latest information…let’s talk about fall weather in the northwest during a La Nina year.
Image number one here tells us what we need to know. During a La Nina fall, the only places likely to be unusually cool are places like Astoria and Newport, Oregon. Portland, Oregon and Seattle, Washington. And right along the coast in Northern, Central and Southern California.
And in this second image, we’re looking at the precipitation during a La Nina fall (September-Novemeber). And where’s the biggest chunk of the U.S. likely to be extra wet? You can see it in blue: pretty much all of Oregon and Washington. Ahh, that explains our wet October where many northwest cities are about 150% of average rainfall for the month. So, that’s what La Nina years typically mean in fall–and these have played out perfectly in October with an unusually cool and wet month underway.
La Nina 2011: Update On Strength Of This Year’s La Nina & The Impact
- As of mid-October, this is still a weak La Nina
- For the first time with this La Nina episode, a few forecast models are predicting we could end up with a moderate La Nina. If this happens, it increases our chance of ‘significantly above average’ snow pack in the Cascades. It also increases odds that cool & wet weather continues west of the Cascades in Oregon & Washington.
- Also for the first time with this La Nina episode, at least one forecast model is predicting this will become a ‘strong’ La Nina, matching the strength of the 2010-2011 episode. If this happens, odds tilt toward epic snowpack (or close to it) for Cascades ski resorts.Â
For now, just plan on an unusually wet and cool remainder of fall. And I’ll keep you updated on the developing La Nina of 2011-2012 and its impacts on the northwest!
Hi Mr. Sussman!
I was just wondering if this winter we will have all the snow here(we had19 inches out here) in east Gresham as we did in 2008. I like to be prepared for winters nasty weather(but I all ways have a plan B if the first one doesn`t work).
Hope you have a Great day.
Ren
Hi Ren,
Valley snow is very tricky to forecast. The odds of another 2008 event are low because that was a 50 year cold snap and 40 year snow event. But…never say never…especially around here, right? But to answer your question directly–we’ll give you as much notice as we can about any big snow storms this winter. And to call those, we need to be very close to the event!
Thanks for your post.
Hi Bruce; I’m getting conflicting messages here when it comes to the predictions for the coming winter. You’re saying we can expect wetter than normal months ahead (I’m assuming southern BC would have similar conditions as Washington and Oregon) but just a few days ago I read that “Accu-weather’ is forecasting a drier than normal winter for us.
Hey Roland–
Right now I’m leaning toward slightly wetter than average for Oregon & Washington this winter–but that may change based on how La Nina strengthens (or does not) between now and winter. I think Accuweather’s point is that a weak La Nina would theoretically increase the number of cold snaps you see in B.C. – and since colder air tends to be drier – your overall trend is drier and colder for the winter. It’s an interesting theory, for sure. And since you’re closer to the source of cold, this theory would apply more to you than to those of us down south. Does that make sense?
Anyway, it’s all on paper for now. We’ll see what happens as the snow and rain hit Stanley Park this winter! Thanks for your great question.
Last winter revealed how deceptive the ENSO event can be in predicting a winter’s behavior. There was so much talk about how the 2010/11 winter would match the 1950 winter. But, the ENSO is only ONE of a million variables in a winter. The North Atlantic Oscillation seemed to steal our big winter hopes in the Willamette Valley. We had ridges all winter, and the midwest-east had the troughs. Lots of teaser events led to a thoroughly dull winter.
I just hope the stars align for an epic ‘2008’ style fall/winter this year.
Paul–
You are so right that there are a bunch of variables out there. It appears the NAO also locked us into our wet spring last year. But overall I felt like last year’s La Nina delivered on its promised of near epic Cascades snow pack.
But we were left out down low. Now, if we’re going for another 2008–let’s do it in one big storm then melt it down–4 days max. That way we can all keep our lives on track, ha-ha…
We’ll see. Thanks for the post!
are we going to get alot of snow in the gresham OR area this year and i hope you can make it happen so i can have a white christmas this year because i want to see snow. can you tell me if we might have snow or are we going to have rain all winter?
Marcus–we’ll just have to wait and see what happens. But if I had a ‘snow’ button back here–I’d push it a couple of times this winter, at least!
Hello, Mr. Sussman,
I have loved weather since I was a kid, especially, of course–snow. My Grandfather, who was born in 1898, told how he drove a team of horses and a buggy across the Willamette River in Wilsonville. The river had completely iced over. I wonder if such a thing could happen again.
I have lived in Independence, Oregon, near the Willamette River for over 10 years. Even when everyone else had over two feet of snow all around us, we had snowfall which didn’t stick. We couldn’t even make a snowman!
For a few years the kids trucked snow to our lawn so we could built a snowman. lol Anyhow, my question is this–what are the chances our little pocket of the world might see some snow this winter?
Thanks!
Beth
Ok, so I have been watching variables from several sources and they all conflict with each other….
Some point to what you say, and that it will be a wet winter with little snow hitting the valley floor, others are saying that the normal La Nina system south of the US is weak where as the northern systems up near China and Russia are extremely strong and could move in over Alaska and the west coast as early as the end of November giving us a system that could put ’08 to shame for snow-pack.
And then there are a few that, like you said, just show a higher than average snow-pack in the upper elevations but a wild and wet valley floor.
My question to you, as I have been called -the weatherman- on many occasions for being able to tell the forecast without using radar or other such tools, but with most of the signs pointing to a possible winter to put ’08 to shame, why not just be blunt and save people time and let them be prepared by saying that it is still too soon to tell and be prepared for the worst? Early intervention in cases of severe weather events can save hundreds of lives, so by saying that it is unlikely to be a year like 08 that was in your words “a 50 year cold snap and 40 year snow event.” is unrealistic if you go by all of the models that are available.