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Speaking of AAM

Ha ha your funny! Yes the low AAM state is more Nina like. So the talk was about the AAM state. I know Ventrice talks about in the winter as does HM, and others. Seems to add a spark to the atmosphere as well. The link in the article above talks about it and is interesting. To thicken the plot though I read that there have been winters in the East that were cold and snowy with a low AAM. However these winters were many years ago, not sure whether they can add value now in this day and age. For example, this came across my mind regarding the the great winter of 95-96 which was a Nina wondering what the AAM would have been then ? I imagine you also have to think about the Pac in years before 95 -96 as well. What was that Nina following up on. I know that enters the outcome as well. The Nina state would suggest a low AAM state but was it? I am sure too the lower solar cycle at this time and the QBO were at play as well.

An interesting older article on AAM . Some things included in the article are the Nina connection, wind fields and workings if it . Some cool images too. https://climateimpactcompany.com/wham-bam-aam-explains-hostile-global-weather-january-2018/

A little more on snow cover advance last week via member bring back 62-63 from 33andrain <<< Now this "temp trend" is a key chart, particularly early on in the re-freeze season. This allows for the rapidly falling "mean" temps during October. If all else was equal (which it never is!) the whole chart would be blue! Again, most of the Atlantic side of the Arctic will see steady short term cooling. Interesting that much of central/northern Siberia will see a warmer period following the cold and early snow accumulation there (more below on that). Contrast that with the top chart. The deeper cold is shifting to north and west Russia and good to see northern Greenland getting very cold. The pressure charts for the next week to 10 days (not shown) show a mix of HP ridges and relatively weak LPs with no serious WAA and no major storms in the Arctic. Overall, although the re-freeze will slow down on the far side, much of the rest of the Arctic should see the rate increase substantially and that curve on the graph (top chart) "should" see a steady rise during the next few days. Let's hope that the recovery rate continues to rise during the second half of October. Last Sunday I posted the Siberian snow cover extent (see chart copied below) and the chart above shows that this has continued to increase - in fact it paused for a few days and then resumed its steady spread south westwards. Given the higher temps expected in Siberia this coming week, I would expect little further growth in Siberia but with much of northern and western Russia becoming very cold and an LP system pushing eastward through Russia around mid week we should see substantial snowfall there and the main snow area should expand steadily westwards. This will lead to the Eurasian snow cover being well ahead of normal for mid to later October. Overall it is a very mixed picture but with no cause for extreme pessimism at this stage. Displaced Arctic cold may provide lower temps in North America and Eurasia but it is bad news for the Arctic. The consequences for the impacts on ocean-atmosphere interaction and disconnects and changes to the jet stream are the subject of a great deal of research and no firm conclusions are yet available. I will place more of the recent papers on this into the Research Portal in the coming weeks and then I'll review the most relevant ones in several post >>>

Hey @poolz1 are you familiar with AAM, angular momentum ? I read a post at a another board from a good contributor and he mentioned we are still , momentum wise no where near a Modoki Nino . He stated momentum is very low and even with typhoons and other features it remains low. The person made some valid points. i think this was the same issue last year. I wish HM would for once post here and give a brief explanation instead of just the twitter world.

A little more on the warm blob...... I look at this feature myself with interest, but its changing now and will do so more in the weeks and months ahead. I would never put a lot into this feature as hope to a colder winter in the East, and as many have already commented, iis it a reaction to a pattern versus a pattern driver. Different views on this one. I like this post by Snowy Hibbo from 33andrain <<< I’m not quite so sure I’m really confident in the Pacific regime either. Firstly the “blob” is weakening and is forecast to continue doing so over the winter. Start of August: A few days ago: The big problem with the present SSTAs is that the warm manifests at it’s strongest around the Aleutians, rather than the Alaskan region focus that we want. The anomalies themselves are weakening quite a bit. And the forecasts I am looking at show some sort of gravitation towards Alaska of the Warm SSTAs, with the Aleutian warm SSTAs subsiding quite a bit. This may make the synoptic pattern better for the Eastern US, but still the positioning of the last month’s worth of blocking is not ideal. So it’s improving, but the strength of the anomaly also may decrease in comparison to other winters. And it also depends on the AAM and associated factors, an Aleutian low may come into play if we see more positive torques and a possible tendency towards a +AAM at some point. >>

Thought this post by Tip over in the NE forum hit home, talking about the lack of Nino coupling last year, combined with folks using analogs associated with Ninos from way back in the day when those are more likely not going to work in our current warming climate regime. Hey, that was my take. To me at least this winter we avoid the basin wide bath tub we had in the Pac last year. Here is Tip's post: Which again... folks may very well observe ENSO as less coupled to the atmosphere in present eras moving foward because of that, for SD events that fall below a certain magnitude. I keep pointing this out... but, few seem to acknowledge it before resuming the same mantra and reliance. But last year ... it took until mid to late February ( as NCEP noted ) for the atmosphere to demonstrate any response/coupling to the state of the NINO fields. It's one of the reasons so may forecasts busted from the private/novice sector - because those linear reliance' are all f'ed up now; the correlations don't work as well, when they are related to the previous 100 years, when the last 20 years of which are hockey-sticking. This isn't just superficially plausible jargon - it's physically sound and being noted by agencies. But, if we want to just blink twice like robots stuck in 'does not compute' feed-back loop and fall right back into that +5/-5 ENSO stuff... okay. It's just that after all, this season outlook stuff is speculative - it's nice for the sake of cogency in my mind if folks actually begin to acknowledge this possibility. Even if we want to say, I am not including for now but it is possible - something. I think there is nothing wrong with forecasting SSTs mimicking a weak warm signal, while the atmosphere behaves like a La Nada? ... I guess we'll let the chips fall where they may... But, that means that other factors ( like the EPO/AO/NAO arc) may be more representative. It's fascinating stuff -

Read some posts that the oceanic SST models might be coming out with the + NAO winter look due to the highly + IOD. That may be the factor among all others driving the look you see on the UKmet too. However, as we get deeper into the Fall it should weaken . Certainly it is a huge driver right now without question. We can get a cold look without the -NAO to help us here in the Mid Atlantic as you know, through a - EPO delivery . Question is what favorable form does the Pac show us in the D J F period. Hard to say right now. And, I assume we get a nice look from the Pac from time to time. There was a great post on these very things I wrote about will try to find it and maybe bring it over.

Good post courtesy 33andrain OHweatherMember Meteorologist Posted 8 hours ago Something like the UKMET isn't far-fetched if the NAO is positive this winter. It has a ridge over the NE Pacific, and would likely verify colder from the northern Rockies to the Great Lakes than the model implies, but would be up/down over New England, Ohio Valley and the northern Mid-Atlantic (averaging mild as a whole) and warm over the Southeast. It's the same pattern we've seen a lot since 2012-13 as discussed on the previous page, but without big blocking to push the cold anomalies farther south. The NAO forecast this winter is something. One of the prominent methods will be very wrong. Analog/statistical methods generally point to a -NAO, while the dynamical models (with the occasional exception of some CFS/CANSIPS runs) point to a positive to strongly positive NAO. Given the analogs and general blocky nature of the pattern over the last few months, it "feels" like we'll see more blocking this winter than the UKMET has, but I would say confidence is much higher in a -EPO than a -NAO until the NAO goes negative and stays negative.

Awesome time loop

Keep it coming HM. I have been reading form other sources as well that so far we are doing very well with NH SCE .

Damn, the CFS is trip'in

More on the QBO, this is a great post by Sam ! I am starting to feel pretty good about the upcoming winter. And HM's take on it .....

One last surfing trip maybe late month.... looks to warm up nicely.

I can't be sure, but reading his post, to me at least ,he seems to imply those years he used are the best QBO matches, not his list for the upcoming winter of his best analog matches . I believe he puts out a prelim outlook early Nov.

Cool and informative QBO focused post brought over from 33andrain. Snowy knows a lot . Of course, as he mentions, just one part of the puzzle. . Snowy Hibbo Posted yesterday at 07:11 PM I think I have my QBO analog. All the years that fit my current forecast for +5 to -10 for this season for QBO values at 30mb, minus strong Ninas and Ninos. My QBO forecast for the next year is the red line in this image, courtesy of FU Berlin. Key trends to note: -NAO, deep Greenland high. Massive European trough. Deep troughing around Eastern US. Aleutian ridge. Eastern US pattern driven by NAO. So not exactly the most sturdy idea, but certainly quite a hopeful pattern. Certainly aligns with the current -AAM situation as well, provided that holds into winter. Of course, just one piece of the puzzle.

Warm up late October then a big change possible in early November ..... eye candy and speculation of course on the long range models. Similar time frame to 1995. Again speculation of course. Will be fun to watch.

HM believes it is a full on Modoki , one interesting element is the Modoki back drop combined with the warm GOA and any interaction between them. Good thread here with replies.

Eye opener from HM

Better late than never. This is interesting as well image of above for Sept 2019

Snow cover continues to expand, looking really good so far .

From a met at 33andrain Posted 15 hours ago To piggy-back off of the above posts...The analogs that end up blockiest over the course of the winter have an Aleutian low and Niño-like tropical forcing in the fall. With the recurving Tyhpoon (coincident with a strong East Asian Mountain Torque) shocking the extra-tropics into a higher AAM/more El Niño-like regime, snow cover advance over Asia supporting continued descending Siberian highs/mountain torques through the fall, and strong sub-surface warming in the central Pacific recently, it looks good at this point for a blocky winter IMO.

This is a great thread to read. Really does seem things are coming together for a Modoki Nino .

This will be interesting to track in the months ahead. I know several mets who are very interested in the QBO and the impact it may have on the upcoming winter.

Heard this has to do with the recurving typhoon and this time the West chills and snows and the reaction in the East is building warmth. I read , as you know , you don't always get a trough in the East just because there is a recurving West Pac typhoon.