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Wow, this is a huge surprise, and then again not so surprised. I value your research and insights, thanks for the time in putting this together @Isotherm Personally I feel we do a generally normal winter but we can revisit this in later March. Isotherm's Winter Forecast http://www.lightinthestorm.com/

Hmm. interesting just apply some pressure and keep it weak. Remember there is talk that the seasonal models may be getting the idea of a + NAO and a + AO from the forecast of a very strong winter PV this coming winter. If that is true, and the PV is weaker instead, we might be a different outcome. Read from BAMMWX that SST models and the data from them that goes into the seasonal models ( and also SST ocean modeling in general ) is prone to significant fluctuations regarding accuracy. Many times the forecast for a certain SST -state months out in the future never really verifies well. BAMMWX stated they studied this and found only about 19 % of the time was the forecast accurate. I am not sure the details and the specifics, but I found that an eye opener. Wonder how much that data effects the seasonal models? Personally, I am sure it does, as the oceans are a huge weather driver.

Glad to hear you think this winter has potential coming up Bob. The eventual moderation and warm up will make many feel bummed, but it is a natural process. Difficult at this time to pin point when we moderate. Rolling forward the phases and the retrogression hopefully not more than a couple weeks warm up. Where last December we broke records for the MJO being in the wrong phases/very high amplitude this December maybe we continue spending the most time in the colder phases. Certainly it has been going that way to a degree. When the pattern reverts back to more winter-like you have to think we might be in prime time. I also read something recently that stated the progression of the PV is ahead of some other analog years that match up and because of that instead of a early Jan severe snow storm, such as what happened a few years ago, we might get pattern in the third week of December after the warm up. Total speculation of course. That speculation of course takes into view the - NAO in December as you mentioned. Also, read in the winter of 02-03 we had a SSWE , I never knew that. I know your stance on those and I agree sometimes they mess things up for us. Meanwhile you hear stories on the media that cattle and livestock froze as they stood in parts of Siberia and other locals because that area took the direct hit from the effects of the SSW. A SSW is like going to AC and thinking you are going to win. ha ... We have had our share lately regarding globally severe generational winter events taking place in the NH. I think the odds this winter will present some crazy stuff going down. Heck, look at Denver recently! Seems the atmosphere is aligning to severe blocks and a convoluted structure. Thanks for your thoughts Bob ! Now that you are back we can rock and roll . Cheers !

I am surprised DT posted this as he loves the Euro, but then again he has a colder winter outlook. In regards to the seasonal as well, wondering what is more difficult for the seasonal models to predict, the precip tendencies or the temps ? I would imagine one is related to the other, and both could be difficult to forecast. The signal for precip has been there along the East Coast. Also, still reading things about the NAO for Dec. As @C.A.P.E. posted. Hearing the spread for a +NAO in December has been reduced. Looks like Jan has the greatest indication of a positive NAO from some sources and hence has strongly shifted . This entire sequence of events is remarkable in itself because if a forecaster can call the turning point of the NAO correctly , or the mild period coming up that can make his or her seasonal forecast golden. Maybe in the NE , including our region, we get the NAO to go negative in December ( still awaiting on HM's call of a more so negative NAO later in month ) That might help if we lose the Pac. If we get the - NAO in December does it then last until early Jan 20? If so, then maybe the Pac improves and lessens the need for the -NAO in Jan . Honestly, if the Pac is as good as it seems like it wants to be this season, well we will not need the help of a -NAO as much . Some here are more interested in the rises and falls of the NAO versus a continuous trip well above neutral. These relates to possible storm periods. All these things enter the picture as to how the month of December, Jan and Feb will go. Interesting times ahead. For every action there is a reaction. Call the first action correctly and then you might be more likely to call the next couple months correctly. I see some professional forecasters are still waiting to release their seasonal forecasts. Why ? I think they are again searching for the sequence and timing the evolution of the current pattern, and the reaction after this anomalous cold period coming up. It is not very easy at all.

This conversation is too good to pass up . Webb makes a good reasoning for us to have a warm December and if we get the ENSO 1.2 to warm well it could get ugly. For every action there is a reaction. @bamwxcom · 41m Replying to @webberweather Things are a lot different this year though. I don’t think we’re looking at the traditional Dec torch. Reasoning is winded but just looking at the PV alone, tropical forcing and QBO/solar cob argues this year has legit chances at atleast slightly colder than normal. BAMWX @bamwxcom· 38m No denying the risk and general climo of course but if I were to bet against all that it would be this year. If ENSO 1.2 can stay cool that will help too along with generally -AAM. That’s our idea atleast hope all is well! -Michael Eric Webb @webberweather· 35m Oddly enough, when you remove the strong NINOs w/ huge NINO 1-2 anoms from that subset, the warm signal gets stronger in Dec. I have a hunch we're probably going to hit a brick wall at some pt once the tropical forcing shifts back into the Indian Ocean. http://atmos.albany.edu/facstaff/roundy/waves/RMMphasecompslp500ht.html… BAMWX @bamwxcom· 32m That is certainly interesting. The correlations since 2000 argue an Eastern Us Trough. The EPS/CFS weeklies also stall the MJO in 8-1-2 largely for DEC. If we torch this year I think it may never be possible to get cold in DEC again Eric Webb @webberweather· 24m MJO phases 8-1-2 are cold at lag = 0 in the east-central US, but w/ positive lag in NDJ, we're often mild or torching. I also have reservations about NINO 1-2 staying negative for too much longer. Eric Webb @webberweather ·22m Interesting forecast nonetheless, I hope I'm wrong because I've gotten completely sick & tired of warm Decembers around here, 8 in a row and counting in NC.

Brilliant ! Bring on the ice age baby ! Its about time Snow Miser gets his damn revenge !

Well now, I see HM mentioned the rubber band theory. I know he reads these boards. I also know for a fact Joel Myers from Accu Weather really did talk about this as a theory way back in the day. Not sure if HM's post means a moderation and change in the weather is a natural process, or whether he believes we can continue cold, or simply the most obvious might be there is no real support for the rubber band theory. Who the heck knows sometimes with Anthony. But, I love his insights ! I imagine eventually a pattern runs its course.

Maybe even the South gets involved. Goes to show you the extent and degree of the cold air mass. However, as Webb mentions, it is still early November, and what is a week among friends.

@poolz1 So much to look at these days, very exciting times. The Strat takes a back seat to sensible weather and real time events but this is worth mentioning. Speculation on my part, but maybe this either decreases any moderation period ( even though the outcome is uncertain and lag period as well ) and potentially increases risk of more significant weather events here. As Tip in NE forum mentioned any strat helped - AO outcome may simply get lost in a season of naturally occurring -AO tendencies. So far, so good.

Hearing the spread of NAO solutions are larger in this update , going by what Matt posted. I have not seen it first hand. Sounds like the Pac remains good, which makes sense and increase my confidence in colder risks/outcomes. Will be interesting tracking what the PDO does, according to Bob's recent posts, maybe going more positive. A + 1 PDO in December ( from Don S ) certainly makes a colder December outlook more plausible based on his research. I am still riding the +PMM for a cold December , even though it is not as high as 3 weeks ago I believe.

A follow up from John regarding the collapse of the Chukchi Sea ridge. A combination of factors leading to a very cold and active period down the road. Awesome animation too !

Bring it !!!!!

Brought it up in the context of a somewhat similar occurrence, a few years ago when a extremely powerful cyclone went up into the NE Pac. Was all over the media and social feeds. Sorry for not including the reference. Was thinking about it and forget to include it in my post. Anyways, there was talk that winter that it could have messed up the AO domain because of over pumping the heights and messing things up in general. However, IF it was the Fall of 2015 and it was the Bering Sea Bomb then that following Jan we had the spike down in the AO and the Blizzard in an otherwise crap winter. https://www.ncdc.noaa.gov/sotc/national/2016/01/supplemental/page-5 So take from that what you may. Overall speculation about any future outcomes pending the recurve as Webb mentions. Oh, just to mention in 2014 there was Nuri https://en.wikipedia.org/wiki/November_2014_Bering_Sea_cyclone I found this link https://www.washingtonpost.com/news/capital-weather-gang/wp/2015/12/14/bering-sea-bomb-cyclone-ties-record-for-strongest-storm-in-north-pacific/ Dec. 14, 2015 at 2:51 p.m. EST The Bering Sea west of Alaska hosted a whopping storm system over the weekend, with sustained winds equivalent to a Category 1 hurricane and gusts up to 115 mph. Having dropped 49 millibars between Saturday and Sunday, the incredible Aleutian cyclone constitutes a meteorological “bomb” — a storm that drops at least 24 millibars in 24 hours — more than twice over. Early Sunday morning, the storm’s central pressure finally bottomed out at 924 millibars, tying the record for lowest wintertime pressure in the North Pacific Ocean since records began in the winter of 1969-1970. The previous strongest storm in this region occurred just one year ago.

Well................................... this might empty the clip .......j/k

Back - trajectories - pretty cool. For this Sat AM.

Week 44 N Hemisphere Snow Cover just updated, and we are very high compared to previous week 44 over the past 20 years. Yesterday we gained positive anomalies on both sides of the pole ( link below ) Southern Canada did very well over a large region. If anything the Siberian high should be aided by the vast snow cover over there. Row Year Week N. Hemisphere Eurasia N. America N. America (no Greenland) 1 2019 44 31.89 18.41 13.48 11.33 2 2019 43 28.69 16.50 12.19 10.04 3 2019 42 23.49 14.29 9.20 7.05 4 2019 41 18.05 9.66 8.39 6.24 5 2019 40 14.63 8.16 6.47 4.32 6 2019 39 8.91 3.52 5.39 3.24 Wow, positives on both sides of the pole. Looking great so far ! https://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2019&ui_day=307&ui_set=2 More to come for NA

Don't see this every day. https://www.naturalgasintel.com/articles/120102-cold-pattern-shows-staying-power-as-natural-gas-futures-continue-climbing

From Don S. taken with the notion that we are not really sure about the next three weeks and how the PDO might change along with possible blocking, as Don mentions. I personally feel that the record IOD , + PMM , less sea ice over vast areas North of Alaska and other factors point to possibly normal December temp wise. but only speculation at this point. However, as with the upcoming extremely cold and anomalous air mass we could snap the rubber band and go in the opposite direction resulting in warmth returning for a while in December , the extent and duration is again pure speculation. From Don S recent post ( just a section of it ) from the NYC forum : <<< Since 1981, approximately one out of every seven December cases involved a neutral ENSO. In general, a neutral ENSO in which Region 1+2 had a cold anomaly and Region 3.4 had a warm anomaly (as has been the case in the 6 week moving average) saw a warmer than normal December. Such neutral ENSO cases accounted for about 27% of all neutral ENSO December cases during the 1981-2018 period. This data does not consider blocking, as it is too soon to be confident about that factor in December. However, the greatest warmth coincided with a negative PDO while the coldest outcome coincided with a strongly positive PDO (+1.00 or above for December). Therefore, the first part of winter could start off milder than normal in the Middle Atlantic and southern New England regions. >>>>>

There are signs that the PDO region might become better established and grow more + in the next several weeks. Also, you have to think that we are deviating to a degree from the warm West Pac , Cold East by nature of the extreme +IOD and very cool ENSO 1.2. Also, the lack of sea ice North of Alaska and other factors as well suggest, at least the possibility, that after a moderation we may not be destined for a torch December. The record IOD is a huge player and even the PMM has my attention.

Valid point. There are however several good reasons to to be hopeful for an averaged winter -AO. I am most interested about December, but you have to love seeing the atmosphere cooperate with the early season cold delivery, Seems if we maintain no negative surprises we roll into December and then hopefully rock and roll near the holidays, none of that post 12/20 warm up crap this year please.

An upper air feature, low pressure disturbance, that move out of far W/NW Canada going SE ( quickly ) and passes over the province of Manitoba, Canada. These features can at times drop far enough to our South and Southeast to spawn cyclogenesis. If they drop far enough to our South and the pattern is conducive they can develop into powerful East Coast snowstorms. Sometimes these storms can even stall or loop as they move NE along the Eastern Seaboard dropping feet of snow. This diving system out of Canada shares common characteristics with Alberta clippers and even Saskatchewan Screamers. The name given simply implies the location they pass over. Great link https://www.9and10news.com/2011/01/03/alberta-clipper-saskatchewan-screamer-manitoba-mauler/

So, then for me after looking at this beautiful meteorological artwork is, what about the eventual flip, and do we go back to a favorable pattern at some point ? I think any relax is minimal, but has to happen. The ensemble mean, as Maue points out, is remarkable. Lets not forget in the process of all this cold is the building snow cover extent and depth to our North and Northwest. I did read one thing from HM about N Pac ridging. However, I assume if that were a huge concern for December in the East Anthony would talk about it more. Here is the snippet from HM I was referring to: << . Too much ridging in the N PAC and you end up with a 1990 situation--big +AO next month. >>

Here is that time period John was mentioning in his post earlier today. I would say you have to consider this as a potential snow event window as well, even though it is way out there. Of course this potential event may favor regions North of us, but plenty of time to work that out. One thing of note, the continuous anomalous cold air from NW Canada feeding down the next 10 to 14 days. On a side note, I have heard from several respected mets that this winter will feature a few robust clippers and even Manitoba Maulers. I would love an exploding clipper to bomb out off the Va Capes and then doing a loop off Ocean City, MD for say 24 hours. As John stated : " Another threat for winter weather could evolve in the Northeast states from 11/11 - 11/13. As the closed ridge near the Chukchi Sea collapses, increased momentum/amplification could occur. The evolving waveguide could support a storm threat a few days later."

Cool animation John created here. Certainly seems there is potential in this time period.

@poolz1 This is a cool post I brought over from @Typhoon Tip in the NE Forum Someone asked about whether there would be a warming event by the end of November , here is what Tip wrote. To me the image and the time issue involved is very interesting. And, as Tip mentioned, in this upcoming winter we may not even need a warming to get a - AO. Sounds good to me . Here is the post <<<< If there is one, keep in mind that there is a coherent time-lag in the statistical correlation. Any subsequent forcing on the Arctic Oscillation lags by as much as 20 to 30 days. Few know this, or, demonstrate very readily via turns of phrase and deliveries of prose where they've beautifully ( otherwise ) fused the sudden stratospheric warming sciences into their speculative, and I'm like " ...you do realize the effects of SSW are outside your forecast range, right?." There is a particularity that needs to be observed, else ... whatever is being observed is more likely to fail coherent forcing on the AO outside of coincident index numerology. The warm plume has to propagate downward in time ( i.e., 'downwelling' ). In every case of SSW graphical layout back to 1979, this downward motion appears to 'spiral' away from a central axial point that begins near the axis of PV rotation, at a very high beginning SIGMA level - typically between 5 and 30 hPa. As it descends, it will first appear to weaken, before the next node comes in warmer, then fades slightly ... then warmer, each node gaining x-coordinate distance upon each emergence. That growth in the x-coordinate is a representation of gaining distance from the axis of rotation. Notice the ending node is almost faded/indistinquishable in anomaly relative to the surrounding features of the ambient field ( nearing 150 hPa SIGMA) there bottom right along the nodal curve. That is tropopausal mechanical absorption/ increasing stabilization and suppression of the depths ensues, and that weakens the PV ... "pancaking" and blocking in the mid and upper troposphere ignites. This entire translation of events, as you can see took ~ from Jan 15th to the end of February ... and we can see in this case a very clear and coherent AO correlation taking place: 2013 -0.610 -1.007 -3.185 0.322 0.494 0.549 -0.011 0.154 -0.461 0.263 2.029 1.475 ... Bold is March. SSW don't really value-add like the popular mantra of the day has it in their mind(s) and bandy about. If one did take place in the last week of this month... We may be hearing about an AO response some time after Christmas.. which is fine. But, I also offer that this particular year we may not have much trouble with AO being negative anyway, so it could be lost in the din of a -AO complexion hemisphere anyway. >>>>>>>