snowman19

The strongest -IOD since 1996 is earth-shattering

I would agree. @40/70 Benchmark has mentioned a few times that the indicators are not screaming KU’s barreling up the coast and dumping on the I-95 corridor. Especially with a very muted STJ (Niña/-PMM)

Not earth shattering. I don’t think anyone here expected a severely negative PDO going into winter. Everyone I’ve seen has been expecting a rise from the severely negative levels. The only unrealistic expectations I’ve seen have been on Twitter….we had some twitterologists back in the spring expecting that we would be in an El Niño/+PDO with a “grand solar minimum” right now….

@Bluewave

I was going to say it’s been a long time since we’ve seen this much cooling in the NE PAC and it’s still ongoing

Those enhanced trades in the CPAC are destructively interfering with MJO propagation, which is why it has really slowed down. While I believe it does propagate into phase 6, I have serious doubts as to what happens once it starts getting into phase 7…

It’s showing an east-based -NAO for December

Agreed. Unless we see a major SSWE and SPV destruction or close to it, I don’t see how we avoid a canonical La Niña mid-late January and especially February and March

Verbatim it looks like a classic canonical “front-loaded” La Niña progression

I wasn’t insinuating that 2nd year Nina’s are bad. It’s 3rd year triple dip Nina’s that tend to be bad. As far as the IOD I would not say it’s voodoo. Definitely not voodoo like the October Siberian snowcover debacle at least

I forget which winter it was recently, I’m sure you remember, but the models kept incorrectly showing high amplitude MJO waves barreling right through phases 8-1-2 over and over all winter long (EPS in particular), in the long-range which never actually happened. They also kept showing phantom SSWEs and record weakening of the SPV, which also never happened. It was brutal, everyone kept falling for it….

I’m not saying that we won’t see +PNA intervals, I’m just doubting that they are very frequent/long in duration. We both agree that we won’t see a 2022-23 style nuclear RNA. My reasoning: 2nd year Niña and the continued North PAC cooling since September 1st. Guess we’ll see what happens soon

I agree with probably 95% of your thoughts on this winter…however, I do part ways on the PNA. I think it’s going to be significantly more negative than you are thinking….no, not 2022-23 negative obviously, but yea

The BOM model takes it weakly into phase 7 before it dies out

I guess some people just looked at the -AO/-NAO part of Eric’s post and looked no further. He has some real ugly analog years in there….1988, 1999, 2011…. See:

This feature appeared at the very beginning of September and has basically been semi-permanent since. The models continue it right through mid-November and beyond. Should this continue into the tail end of this month, I think that would be rather significant. @donsutherland1 @bluewave EDIT: @mitchnick Wrong. He’s also a meteorologist. Guess you didn’t bother to read that part in his Twitter profile

My best guess right now is that it dies when it hits phase 7 then ends up back in the IO

I think it does get into phase 6/7. My big question is what happens when it reaches 7

The Northeast Pacific continues to cool, the “blob” area has cooled over -1.25C since September 1st. While these SSTs are not driving the pattern, it’s indicative of a longwave pattern that favors cooling in that area. If we get to 11/30 with no sign of this trend completely reversing, it’s going to become very difficult for people to continuing using years that saw SST patterns with a “warm blob”. To clarify, I’m only speaking of the people who are using SST analogs with warm blobs, not other factors (QBO, solar, PDO, AMO, etc.) to justify certain analogs

The IOD is peaking right now. It’s at -1.94 through 11/2 and expected to peak by 11/10. With the ongoing cooling in the WIO and warming in the EIO, I expect it to bottom out on the next weekly update at or slightly below -2.

At absolutely no point did I ever say it wouldn’t be a weak La Niña. Never ever, not once. However, it is much, much better coupled than last year at this time

In particular, when November sees no measurable snowfall then December goes on to see below average snowfall during a La Niña, it very strongly corresponds to a below to well below average season. Obviously not 100% and I’m sure people can find exceptions to that rule over the course of 100+ years of weather record keeping, but as a sweeping generality it works very well

Is the PDO weaker negative than last year at this time yes. But the La Niña is much better established this time around than last year, which was a late bloomer Niña…cooler Nino region SSTs, EWBs/enhanced trades started earlier this year, the eastern PAC (GOA, along the west coast of NA and down to Baja) is cooler and there is a very pronounced -PMM (very supportive of Nina) whereas last year we had a +PMM at this time. Also, much deeper and well established +SOI and a deeply negative AAM (Nina). Would love to see what the MEI is but that doesn’t update anymore @GaWx Edit: The deeply negative -IOD speaks for itself as far as being very supportive of La Niña/constructive interference

Correct. A cold western IO and a warm eastern IO is textbook negative IOD. If you notice on the SST charts, the western IO is still cooling very rapidly. I believe we are nearing the peak, probably within the next 2 weeks or so and I have very good confidence based on the ongoing cooling and the last weekly update that this event reaches or exceeds -2, which would make it one of the strongest -IOD events in history. It already set a weekly record (since 2000) on the last update

I’m starting to really doubt the MJO wave makes it past phase 6/7 before it dies and ends up back in the IO. I think it’s a combination of the record breaking -IOD and the rather healthy La Niña we have Saw a tweet this morning from someone who was perplexed at how weak the STJ has been….not really a shock with a Niña and the strong -PMM that has developed