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A few interesting things to keep an eye on : The mid month period when there are signs of a drop in the AO along with a +PNA interval. Some favorable action too from the strat may work its way down to a degree. Meanwhile, interesting progressions with the warming as it transpires in terms of the Canadian vortex and trop / strat vortex over Siberia/Scandy , as mentioned by Hugo. Also, the elongation and the movement of the trop vortex has my interest as well, in a backdrop favorable to keep the vortex perturbed. Below are several relevant recent releases on the above.

Maybe we get lucky with some snow showers this week, but the way the current pattern looks, I think we need to wait a while. The various indices that are normally associated with accumulating snowfall in the Northern Mid-Atlantic our not in our favor moving forward. Yes, I know about scoring in flawed patterns, but with the time of the year, I have less confidence that happens this go around. The end of the month still seems to be uncertain, maybe we turn colder with opportunities later in the month.

I will gladly ride the BAMMWX train ......................where can I get my ticket ? By the way.....I still believe in snow and in holiday spirit. Hopefully, a nice time coming up for us soon for those who enjoy cold and winter scenes of snow covered fields and streets bounded with snow in a winter wonderland.

I admit there are some positives but as you know the GEFS is at times biased weak, at least so far this early season, while the EC has done better in strat verification forecasts. However, as you mention, we are talking under 7 days here with the GEFS, so that is a positive. Also, according to Simmon Lee the FV3 GFS has been doing better versus the GEFS. A quick note on the AO ensembles - seems the forecasted extreme positives, up to +5 or more, have been trimmed back down to about + 3, with several members taking the AO back negative shortly thereafter. As HM stated previously, the same processes causing the AO to rise will be responsible for the upcoming decline in the NAM state. Meanwhile, Matt is impressed by the potential down the road. We will also get an update soon regarding the QBO. There are some interesting evolution and progressions possible in mid- January if things work in our favor. This is of interest as well :

I understand your point.

Sorry, nothing is bogus here. Research is convincing that during this decade there has been impressive warming in the Indo-Pacific warm pool and changes in the behavior of the MJO. Since 2010 there has been a tendency for repetitive Fall patterns. If you don't agree with the data that is fine.

Do you follow Isotherm? I know he has spoken about the solar cycle and in various posts he has alluded to role the solar minimum has on potential impacts within the NAO domain. His seasonal prediction of the NAO has a very good record. I found some articles/research that seems to reveal a link between the years after the solar min, and the phase of the NAO. The interesting part is the lag effects. Seems it could take a year or two, maybe even longer for the impact to be reflected in the NAO domain. The link was SST based I believe.

I brought it up because it has been repeating lately in some form or fashion ( a 2010's weather theme, and you can read more about MJO study here ) https://www.nature.com/articles/s41586-019-1764-4 and this from @bluewave Yes, I just posted that in the climate change forum with all the charts included. The changes to the MJO have become a big part of our 2010’s weather patterns. It shows what we already figured out. The MJO has been spending more time in the Maritime Continent phases due to the rapid SST warming of the Indio-Pacific warm pool.

You believe we follow the same general progression this winter? I feel we will, but the colder risks will win out once past early Jan. Also, speculation on my part that we will deal with some significant phasing events and some very cold arctic intrusions. Simple guesswork reveals the best -EPO period/events in mid- Jan, and the best -NAO event in early to mid Feb and another opportunity in March. ( March to a degree dependent on the declining QBO and any SSW in late Jan. and early Feb) again just some thoughts there.

The much anticipated warm December is coming. Simply can not fight the deep tropics. The same concerns last year regarding the MJO that lasted in the warm phases for weeks on end may repeat again this December. The latest AO forecast do not look as good today, the NAO going up. Source regions are warming. The camp that predicted an overall warm December is a step closer to possibly being correct. Early December this year similar to last year, and then we warm. Whether it lasts two weeks or longer is still hard to pin down. The consistency of the last few years of the pronounced warm up post 12/20 is an increasing risk again this December. There is a repeating pattern of late.... warm Octobers , cold Novembers, Decembers turning warmer after the first week. There could be a delay this December with the cold winning out until the 10th, but still looking like we warm once past the 10th. I will also mention new research reinforces that the idea in which the MJO is spending more time in the warmer phases while racing through the cold phases. This is pronounced in the time period from 2010 forward.

There does seem to be some differences to last year at time, with possibly a bit less amplitude. Last year was agony though, with the slow progression through the warm phases, and that lasted well into Jan. if I recall correctly.

Do you think we ever see this trend reverse ? And, would you speculate that it can potentially reduce the chances of an extended period of severe and durable cold weather locking in here in the East , of the magnitude we saw at times in the late 1970's ?

Wondering whether this new research has a link to warmer temps via the MJO phase progression, and the shortened period of cold, regardless of time of year, due to the fact the MJO is spending more time in the warmer phases, as the Indo-Pacific warm pool is effecting the MJO via progression and life cycle. research link https://www.nature.com/articles/s41586-019-1764-4

Interesting post by Isotherm from 33. Posted 1 hour ago Other proxies of northern hemispheric, vortex status indicate the predilection for lower-geopotential heights in the Arctic domain, but particularly the NAO domain in the means, as delineated in my outlook. November 2019 ozone data evinces generally lower concentrations near/over Greenland to the north of Europe. When juxtaposed with the mean November climatological ozone, it has generally been less extensive in those domains. Moreover, the polar vortex area is now running well above normal, circa 30 million km^2. Expansion in vortex area is generally a precursor / presages tropospheric NAM significant incline. Again, as Don alluded to above, while aesthetically pleasing stratospheric maps continue to be circulated, it's integral to examine exactly what is transpiring in the troposphere as far as the veridical data. SPV intensity diminution doesn't always correlate directly to tropospheric vortex status.

I am looking at zonal winds at 10 mb. But, as you mentioned , and also brought up by HM indirectly, is this set-up forecasted by both the Euro and the GFS. On a side note, I have not looked today, but hearing the wave 2 follow-up may not be as significant then first thought for early to mid- December. A lot will change moving forward, no worries there yet.

And yeah, steady as she goes .....

The way things are going right now with the vortex is probably the best outcome, more or less. Speculating that we don't have a major SSW in December, ( at least that is what the current modeling shows and echoed by some strat experts ) Sometimes the rare very early season SSW can interfere with things and many times the vortex recovers. Having any type of major SWWE later versus early can possibly extend our winter weather potential. Of course, we would have to be lucky in that respect and be the area of focus. And, I know you know this poolz1 , but we have already experienced a minor warming and it appears yet another minor warming is anticipated in the first half of December. So things are looking good a bit down the line. Oh, and for the record, I feel robust blocking returns and coincides with a split flow pattern, leading to a memorable period of winter storms in January and beyond.

I hold no real value in the CFS, but I appreciate your post. I too have seen it actually be in the forecast month and calling for significant warm anomalies and the country is already cold and only getting colder. Maybe use it for trends and know it is extremely volatile. Never hang your hat on the CFS, unless maybe you are attempting bias in your point of view. Same thing for the weeklies. However, I still believe we warm up prior to favorable changes in the MJO, and other factors. Using lagged MJO composites and relevant analogs there seems to be a good case for blockiness to reestablish itself in early January, ( maybe as early as the last week of December ) along with another -NAO interval. Some of these analogs indicate the cold locking in and persisting in time. The greatest -EPO in these are Jan targeted and the deepest -NAO is mid Feb.

According to Don S it is entering the time period when it is more skillful. Well, I am not sure verification from this date, November 27 for the next month, but I believe we are still going to warm up in time for the holidays. As for how warm, and how long, still hard to say. We lose the - EPO so maybe Pacific based air mass floods the country the third week of the month. I am liking January and Feb.and even March, the new winter month, thinking March holds above normal winter weather promise this go around.

Wish HM would pop in and chime in on that map, from a HL point of view. . I might want to guess and say it looks at 500 as a precursor pattern for further vortex weakening.

Very true, it has been so long that we have had all the players working for us in our favor. ( ie. the 50/50 or a -NAO leading to a HA event, etc. ) I miss the Big Dogs ! The atmosphere may want to cooperate this winter.

Thought I read this might be related to the SST profile up there. Over the summer when we had the periodic bouts of -NAO it was mentioned the cold pool was responsible. Do you have any thought on it psu? Secondary guess would be wave breaking, but not sure. And yeah, love seeing this.

The 50/50 is so important for our area it is featured among DT's checklist of MECS. I know he loves focusing on the QBO, but when he goes down his list of key features needed for the big ones, the 50/50 is always talked about in detail. The throwing rice at a wedding thing was a good one ...... I love these HH runs !

Some mets are looking for their return this winter. As mentioned a while back, some pros and certain seasonal winter forecasts have mentioned better odds this winter of Alberta clippers, etc., would love a Manitoba Mauler that cripples the Northern Mid Atlantic. As for where have they gone, seems since we had that massive warming in the Pac a few years back , it has been sort of blah, just speculation really.

Frequent coastal storms and even this development here points to an active winter in the East according to a few mets, and I am beginning to believe it more and more. If those whom are calling for even transient -NAO blocks in our favored areas this winter are correct, we might be very happy snow-wise during our better climo period. Between varying the NAO domain state, and more than likely having an occasional split flow pattern / active STJ moisture, should present opportunities for us.