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Awesome stuff here. Love it !

I hope the "weaklies" are wrong.

Interesting, wonder what will happen when the record +IOD starts to weaken or the Eastern region 1.2 becomes colder. I believe 1.2 is expected to get colder again later this month. Also, signs down the road the MJO starts to improve. This may coincide with the next attempt of a - NAO , later in the month, or early in Jan. So, there is hope that both the Pac and the Atlantic may both become favorable for a time.

@Bob Chill your call about the +PDO seems to be happening in real time. The November figure was positive. Of course we might improve on that this month. If this oceanic researcher is correct with his formula calculation, then the PDO should rapidly increase in the + range later this month and in Jan.

Thanks for taking the time to post that psu ! And, this is not as bad as I would have thought: Since 1950 the January/February months following a +AO December were 12 negative AO, 16 Neutral AO, 20 positive AO.

To me he talks mostly of pattern drivers and such. I would think that benefits a large area.

I hope HM's hand remains hot at the table.

Bob, am I correct that it will be three more days until the shortwave comes onto the California Coast ? The particular latitude may be a player as well. If so, more changes are a coming no doubt.

I was really hoping once the AO peaked recently we would not have another attempt at a + 3 SD or higher. It appears another run up is possibly on the way. The image below is from the 12/4 , but if you looked today it is much higher. Could not get that to post correctly. Having the AO drop down in November was great, but I believe you can not gather that decline as a proxy to what the upcoming winter may have in store regarding NAM state. Another deep dive in December I would speculate has more relevant meaning for the months ahead such as Jan. and Feb., maybe even March, versus a November dive down. I am sure there is research on this somewhere. I could almost speculate that possibly the drop in November was more an outcome of the combination of typhoon involvement, and early season mechanics. So, I guess more a head fake versus a real signal. @Isotherm , Benchmark or even HM might be able to answer that possibility.

Can anyone confirm these maps were just released ? The Euro Seasonal . Seems new to me, and they look sort of blah with a 2 meter temp signal indicating ridging too far off the West Coast and a slight signal for a SE ridge. Bottom row indicates active storms and precip, but maybe on the rainy solutions along the East Coast ? Same issue as last year possibly with a lack of HL blocking, as I already mentioned earlier today. Looking at this output form the Euro seems it would be similar to last year in terms of the best winter target zone, the upper Midwest and Northern Plains. Can the Euro seasonal be wrong, of course, but balancing things out this continues the theme of high uncertainty regarding the winter. I mean last winter's seasonal from the Euro were so so bullish for snow and cold and then looked what happened. I continue to balance expectations.

The same old story with Decembers and the NAO. Seems no break in this pattern. According to bluewave this goes back to 2013. (see below ) I know there was talk of a wave break and possible interval of a -NAO during mid-month, but I don't see it. Those calling for a -NAO in December of any magnitude might need to reconsider. ( The caveat is no one really can be confident in the outcomes of the NAO far into the future so, my comment is geared to the next couple of weeks ) Bringing up the common seasonal idea is that the most robust - NAO is in Feb and the most robust -EPO is in Jan. However, starting to wonder whether HL blocking shows up eventually, and whether we get a -AO averaged winter. Reading some folks whom tie in the tropics with the HL, they state tropical forcing including AAM and GLAAM are lacking in terms of promoting the mechanisms needed to achieve durable HL blocking, They also state HL blocking precursors will be fading starting now and may last for a while. An additional concern is the warming in the Eastern ENSO region. So make of that as you may, it appears as others have stated, a high probability of not knowing what is going to happen along with a roller coaster of temps here in the East in the coming three weeks.

I am not really sure about what HM is focusing on in regards to the vulnerability of the vortex. When I read Isotherm and a couple others whom really focus on the strat they paint a not so rosy picture. Little to be hopeful about for a while. Even the QBO is not going to be a player until maybe Feb. from some sources. Regardless of whether the QBO is following the linear progression of 2002 most closely, this fall does not have the feel of 2002 and certainly the Nino aspects are not the same. Enter a recent warmer backdrop globally, that comparison losses value, as we are talking 17 years ago. Even though the GFS has short-term skill and is predicting wave 1 attacks on the vortex, the result seems to be more movement of the vortex, displacements if you may, versus a real weakening trend versus what was happening, or starting to happen last year at this time, as Simon mentioned that this morning. This development more closely matches what Isotherm was looking for I believe for the mid month period.

I will get excited when the highest snow amounts in the ensembles are South of us. Seems like the last 2 years the ensembles paint a rosy picture of 4 to 6 inch amounts ( several times in the season ) and they never happen. Worse yet, the 46 day snow total off the ECM, that also seems never to work out. I cringe when I see folks like JB or even Maue post these sometimes. I admit it is entertaining, but hardly ever works out.

Seems that the EPS and the GEFS are worlds apart in the eventual outcome. But, as mentioned already, without any significant help from the NAO or the AO regions any storm will simply cut despite how cold it is close to the event.

I had to read it twice until I realized it was Ji who wrote it . Very philosophical.

@Maestrobjwa I know you have an interest in this, I bring you a couple short posts from 33, one from a very informed member, the other from a met. From Bring-Back 1962-63 Low solar "can" be associated with colder winters. More often the coldest winters tend to be just after the solar minimum. We are right at the minimum right now. There is usually a run of 3 winters which "can" be influenced and any combo of 0, 1, 2 or all 3 can see colder patterns. The last minimum was in 2009 and there was a triple hit. In the UK (and Western Europe) we had a cold winter in 2008/9, 2009/10 and the coldest Dec since 1890 in 2010/11 (although the 2nd half of that winter was mild). From Analog96 DT was talking about that ( this might be a protracted min ) and how it could impact NEXT winter, as well. Now, I just want to point out one thing. Being in a solar minimum does NOT guarantee cold winters. HOWEVER, it biases everything toward colder. Atmospheric indices/teleconnections, etc, still rule the atmospheric response. BUT in a solar minimum, cold teleconnections will verify colder than otherwise, and warm teleconnections would verify "less" warm. Teleconnections that favor average temperatures would probably result in a bit cooler than average.

I don't think the WDI has any real value, whether by chaos or statistical merit. Too short a reference period as well. If you look way back there are periods when many years pass without any real significant snow.

Interesting in regards to the GEFS and the trends in the -EPO

Ugh, we will see. Thanks !

If his formula is correct will be interesting to see the outcomes regarding the warm blob. I know we are talking degrees here but combined with ice free waters near Alaska may assist in blocking. Emanuele Di Lorenzo @manu_ocean Ocean & climate scientist. Dad of four. Professor & Director of Ocean Science & Engineering @GeorgiaTech . https://www.dropbox.com/s/xxuft0mmb3qzvzb/DiLorenzo-heatwave-prediction-2020.pdf?dl=0

How was Jan and Feb 1960 in the East, do you recall? ( silly question , right ;-)

Maybe, as mentioned previously, the start of the less prominent IO standing wave later in the month.

The wave breaking outcome ( IF it materializes) may not show up in the modeling till later. Very complex and a huge timing issue. But, even if this attempt fails I believe there is another attempt at a -NAO later in the month. Also hearing some chatter about the pattern so far this past November and presently is similar to the loading pattern that produces a significant -NAO in January.

This may not be the perfect analogy and forgive me the context it was used in ( top down , or bottom up ) but I read Matt Hugo stating the TPC could topple like a deck of cards in which you unbalance the deck by rotating the cards and it just collapses, once the mass is shifted. Well, I am not sure the context here in this post form Anthony but he believes it is vulnerable. Certainly things are in place presently, and even more so at mid month. to put pressure on the vortex. Even the return of the Sea of Okhotsk Low.

Yes, that's true Ray, I believe your seasonal outlook is more positive for snow lovers and you were more bullish on December cold risks than most out there. The only folks I now that had a normal or even below normal December ( Or seemed more positive about December ) were you, BAMMWX, Analog over at 33 , a met whom posts there, Weather 53 here and HM seemed positive as well. So basically we have two camps on December outcomes. Today even Eric Webb changed his tune as you may be aware. If I recall correctly I believe your seasonal progression may vary a bit from Tom's too, in the sense he seems more bullish later on in the season while you are more positive about December and Jan, although I think you have a caveat about Feb and March could turn out better. So far you are doing well !