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Some decent thoughts here about the NAO from Webb, and what may happen. Plus, a quick one from HM on the same topic.

Check this out, really impressive.

There are signs that a real - NAO may get going to extend the colder pattern in the NE later in November. There always has been talk that later November/early December it could occur. Looks of retrogression in the pattern along with several indicators such as the MJO, Aleutian low, Scand block.

Something else to ponder. A +PDO versus the Victoria mode. You can see the image at the bottom for a representation of the associated SST anomaly . I need to research this more. Maybe Bob can chime in on this. To me the Victoria mode looks like a + PMM a little . I refer you to this https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JD022221 The Victoria mode (VM) represents the second dominant mode (empirical orthogonal function, EOF2) of North Pacific variability, independent of the Pacific Decadal Oscillation and is defined as the EOF2 of SST anomalies in the North Pacific poleward of 20°N. The present study indicates that the VM is closely linked to the development of El Niño–Southern Oscillation (ENSO). The VM may effectively act as an ocean bridge (or conduit) through which the extratropical atmospheric variability in the North Pacific influences ENSO.

Heard that BAMMWX is entering warmer risks into December, but what I also heard was they mentioned the +IOD a a means of possibly lessening the warmer phases of the MJO we are destined for in December. Then this evening I saw something online by DT stating it was good news that in December the highly + IOD is forecasted to weaken. Hmm, I need to think about that more. WXRISK.COM 23h A good point about the positive IOD. The good news for winter wx lovers is that it looks like the IOD breaks down pretty significantly in December

Priceless !!!!!!!!!! I almost needed the Heimlich maneuver as I watched this while eating my dinner .

Hope your new grass survives the winter torch...... keep watering

Yes, that is true for the Atlantic , Matt posted on that earlier. HM posted weeks ago about the coming wave breaking events. Here you go -

@poolz1 You might enjoy this link. There is even a bias corrected 45 day CFS-v2 U10-60 forecasts. Pretty neat! https://simonleewx.com/polar-vortex-forecasts/

Something to keep an eye on during the next few weeks, as it appears to be an interesting set-up .

I know you touched on this already, to a degree, but do you have specific research that shows in this semi-new climate era from say 2010, that when November is winter-like then the winter attempts to mirror that outcome in the following March as well ? If anything, it seems winter starts later, taken into account the November head fake and then lingers longer. The linger longer part I imagine has to do with delayed seasonal blocking and any related lag effects from possible PV weakening. Last March many thought it was going to deliver, but it really didn't to the full potential some said it would, but oh boy April was cold. The year before was an epic March I even think the maturing of the event was responsible for the less hot June and July, relatively speaking. Thanks

For someone with Weather Bell access I am not privy to what the Euro ensemble shows for the AO, but the lastest CPC AO forecast shows more spread today. Can't post the 11/7 update here is the link https://origin.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.shtml

I don't have an answer for this. I know last year Isotherm had mentioned he thought we might be nearing a period of more frequent - NAO cycles. Some research points to the sun effecting the ocean currents in the NAO domain, which can lead to a seasonal - NAO, but in this area I think the lag might be as long as 2 to 3 years. I know HM wrote something a few weeks ago about the NAO , and I personally thought it implied he did not seeing long periods of NAO . Whether he meant that for this month or this coming winter, I am not sure. I would have to search for the post. Here is what Isotherm wrote " There are other factors forcing the mode as well. Furthermore, as a general and practical matter, the descent of the solar cycle tends to force a greater frequency of positive NAO periods. My NAO formula suggests that the mean will be positive for DJF. This is not a deviation from most winters of the past decade. "

Very true. He also highlights on AAM, atmospheric angular momentum and the momentum budget and stuff like that. Hard to say if we go towards his solution. Last year Tom thought we did not need a SWWE , and I believe he might have hedged against a wind reversal and a true SSWE. In the end that did happen. Did it take full responsibility last year for the poor performance of many humans and machines, not sure. Some mets commented last winter the models saw the warming at HL and went with the idea that blocking would indeed develop over the AO and the NAO regions due to the Dec SSWE. It never happened and hence the awesome look by the weeklies and other models never occurred. We have mentioned many reasons why , the pure lack of tropical forcing, the ocean and atmosphere not coupling, the December SOI which was positive not negative. Not what you would expect. The MJO being effected in the warm cycles by the SSWE. The basin wide Nino and the very fast Pac jet, and High pressure in the Central Pac that enhanced a SE ridge. ( Nina like ) Everything went haywire and there was no cooperation and sync if you may. You would have thought the blocking should have descended to effect our sensible weather but many blame the QBO as a road block to that not happening. last Jan. This year we have a more favorable QBO. I also think I read in Tom's winter outlook where he stated in low solar min the NAO is more so positive, not sure but I think I read that, if so, I wonder what makes some solar min winters so freaking cold when I looked at previous solar min winter since 1950.

I liked your post but then I got it ....... so here you go

Looking like maybe we do not lose the trough in the East later in the month. I like the signal for the Kara Sea ridge Also, the consider the MJO as well for later in the month and then continuation of the progression would lead to a warm up in early December.

I don't follow Larry, but I can tell you Isotherm does have a good record at predicting the seasonal trends. His forecast for the next winter is anticipated by many every late Fall.

I post the positives and negatives - for those that wonder why - simply to make sure I am not biased cold and snowy. I love snow, but I attempt to be more realistic as I age. Chatting with bluewave about this November, just like last November we are doing great in terms of almost record high NH snow cover. I use to think that was awesome. What was viewed before as a great signal to a colder winter ( Judah SAI) has waned. We lost the snow last December and might lose the snow again this December if the warm December forecasts are correct. The changing Pac along with lower sea ice and other features are acting to put down rapid snow cover in October leading into November only to fall back versus above normal values in December. Damn I hate looking at those maps. from bluewave: <<< The cold November followed by a mild December has been a very persistent pattern this decade. So the snow extent charts are just reflecting this new regime. >>>

Well you decide. Personally I can see a shot gun of outcomes. What do you think? As HM states, a shoe-in for a warm December , right ? Only a couple mets I follow are going for a normal or colder December.

Pretty impressive SST anomaly and the waters North of Alaska are still ice free. I am beginning to appreciate more and more how climate change is changing the drivers of weather. Not only with recent Novembers but even with how storms are tracking in the lower latitudes. In part from the HC and height field compression .

This is an interesting precip signal from the seasonal . Wonder how active the Northern Jet will be ? Progressive disturbances, versus, do we ever get upstream blocking to develop. Everything last winter either flew by or lacked proper phasing.

Is the EPO loading pattern / low sea ice, other N Pac features forcing these colder Novembers since 2012?

Eh, that stinks and icing on the cake was reading Isotherm's winter forecast. If I didn't value his insights as much as I do I would throw his forecast aside. But, I can't.

Well......... deja vu anyone Just like last year to the date per Bluewave , ( record high NA/NH snow cover ) wonder if we face the same scenario as Dec 2018 come this mid December, when the NH snow cover dropped rapidly. What looked so promising changed so quickly as warmth over spread the land. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

I am sure you recall last year, looked great and was great but we hit the middle of December and poof, we lost a lot of the snow cover in the States and in Canada. Notice that dramatic decline in the graph around the second part of December. We would recover eventually, but not till mid Feb. ironic. Wonder if we are destined to the same outcome this year? You would have thought the snow cover might have aided in the delivery of cold air masses into the states, but alas it seems the ones who did benefit the most were the Northern Plains and Northern Maine.