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Maybe a start.......

Weep and cry to the record negative cycle in the warm season. This is one of the best running representations of the NAO I have ever seen. Two notes, one the record -NAO from Spring to summer, and the other is the ability, at a short range, to forecast the NAO .

Willing to venture a guess when, or if, that wall ever breaks down? Or, does it evolve in such as way, later in Feb. to allow a penetration of arctic air to the lower latitudes via a PV elongation or slight displacement event. I still like Feb 18 th to the 22 nd simply based on previous behavior of the pv since November. The idea which HM brought up, about a strong winter vortex following a certain period of waxes and waning, such as the vacillation cycle near the 20th of the month. As we get to early March, as mentioned previously, the IO signal favors cold and who knows, maybe the descending QBO effect begins to kick in on a subtle scale.

Thanks Tom. Great news to hear. I have to wonder myself the implication of the lag effect and whether next winter might be too soon to achieve it. However, there are couple intriguing elements to consider next winter, one of which is the well established - QBO .

I bet for most areas the biggest negative temp departures from normal occurred during the deep - EPO of November. That was some impressive cold for so early in the season.

Wonder if we do achieve some sort of change with momentum displacement to 40 north and above, as Hugo mentions. A cold or colder March this year certainly seems like a possibility. Cold enough for snow in the Northern Mid Atlantic is the question though. Latest EPS I saw a couple days ago keeps the EPO positive and the AO as well. , But maybe we can still achieve a change for the better in the NAM state later in Feb and in early March.

Great comments here and post form HM. Anthony also mentioned this regarding the IO forcing, that it is a cold signal late in the winter. " ...the other variable is the Feb wavelength, with low frequency forcing of niño, can amplify the PNA pattern. But if this forcing isn't present or reduced and the vortex is strong, it probably won't be a reoccurring feature. IO forcing becomes a colder signal late winter. (2/2) "

Before any re-load of cold into Canada some areas near James Bay are projected to have anomalies in excess of 30 degrees above normal. Pretty remarkable.

I still think we are in a pattern that supports cold dry and warm wet. I know you said previously it is not really a pattern. But, to me how you get there is the same. Fast progressive flow, fast Pac jet, no upstream blocking and hence storms cut to the NW and we repeat over and over. Cold invades but does not last long. Now, with Canada warming we may not even experience that, as it warms so much there is little back and forth. With our luck wishing for precip/moisture does little good as it only supports rain. We might even get a BM storm, but without any real cold it simply rains in the heart of winter. The new era. This same issue plagued us last winter as well. But because at times the cold lingered longer, and we had a period where the pattern was more conducive, we did get more snow. ( Where this winter ends snow-wise who knows ) Not worth the time to dig into it yet. But, if we score big between Feb 20 and March 20th all the failures may be forgotten. Ha ha - who am I kidding.

Tom, if you are able to comment would love to hear if you have any thoughts about a change in the NAO cycle over the next few winters. I have read research about ocean cycles and the AMO as well as lagged Ocean currents in the NW Atlantic as related to the solar minimum. Some are saying we might make an abrupt move to a multi-year cycle of - NAO over the next few years. ( I assume they mean a winter -NAO not a warm season - NAO ) . That would, in my opinion, be a remarkable achievement based on the last 5 years of more. Of note, and whether it is a clue, or even important, not sure, but how about the record number of consecutive days the NAO was negative from late Spring to summer last year. A lot of talk back then of warm season blocking, but not as much -NAO action during the meat of winter. At one point I believe in August 2019 even bluewave posted and commented on the robust deep dive of the NAO and how it effected sensible weather leading to cool weather in the East, during an otherwise hot(est) part of the year. Thanks as always.

Nice to hear confirmation about these features. I believe last winter, along with you, Tip from the NE Forum brought this point up as well. He mentioned that the SST structure/expanse in the Pac was more so a swashing bathtub effect with warm waters over a large area, but no real focused anomaly. Some are saying we need some type of major Pac event to re-set the table. I am not sure whether the talks focused the need on Nina or Nino.

It can't forecast the MJO , or the month ahead weather, and some people really have faith in it. There was a study bluewave posted in the Fall about the behavior of the MJO, avoiding the cold phases and spending more time, at a higher amp in the warmer phases. This has been going on for a while.

Excellent point and goes right to the point about the response ( how much and where it goes ) you get. I have to wonder if there is a any connection, or role with the previous record SSWE in the SH. That was an extreme event and coupled for weeks on end. A pretty site on the charts. I think that deep - SAM played a part as well in the record dry Australia pattern along with the + IOD. How that effected the MJO and the West Pac I am not sure but I do believe there is a relationship as well. Please study that this summer as well psu. ;-)

I like that train of thought. I can see extreme snowfall when the conducive patterns return. Some years huge, well above climo and several below, but in the end averaging to climo. Tom's work is enlightening. The thing that sticks in my mind about his work is the focus he has on the eventual hand off to players that guide a favorable pattern, or reasoning they will not. He and others in his clan of strat enthusiasts focus on energy transport, GLAAM, AAM, the TPV, etc, unusual methods to provide a clue to the coming season. Learned a lot reading his work about coupling, the TPV, energy transport, etc. It should have worked last year, and this year he basically went with the disconnect and he is so far doing very well. He call about NAO is right on target. For him to really do a complete seasonal call and get icing on the cake would be for the pattern to turn snowy and cold in his window which if memory serves me correctly is after Feb 20th to early March. @Isotherm please correct me if I am mistaken regarding my previous statement. If anything the new warmer base state has made the study of meteorology even more difficult , and even more so in the long range field.

Everyone seems a bit aggravated by this winter and the nothing seems to work outcomes.