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Thanks Ray. I was also thinking about the relationship too, outside of just temperture, regarding the implications for EC storm tracks, and SE Canadian vortex placement and even HA events. I guess my thought was, whether correct or not, is a major warming with proper tropospheric response could up the ante on storm intensity, maybe surpression too could be an outcome as well.

Some AFDs were as of a few days ago calling this storm and the predicted snowfall to be a generational snow event. I imagine in some areas it truly is. Add the time of year, and it is an epic.

Mentioned this earlier about the role of the PV. Looking at this view you can certainly see how it crushes the storm from making a significant move North.

Busy at work just checking in, I thought the Euro was going move North. Still seems firm in a Southern solution but what got my attention is something I hardly see mentioned , at least in this case as to why the storm is staying South. I mean I heard the about the NS vorts, the confluence, high pressure and the western ridge too but then I came across some sort of involvement with the SPV . HM was mentioning the " The trough down 60W is part of the full vortex and all of its associated cyclones in the troposphere." Seems that when you look at the SPV in 3D you can see this better. This is the first time I read about this and the 3D look at the vortex really adds a nice visual depicting how it can be formed in odd shapes and changes in height, for example it can be whole at the upper levels and split like a pair of pants at the bottom. You can see it better below in the animations or visit the thread as I don't want to post too many of these. There is involvement here with the pattern and the storm and this is acting a untraditional block I think I guess this sums it up here from HM , " Looking at the big picture, this isn't the most ideal way to slow down the "50-50 low" and suppress a coastal storm (North Atlantic blocking is the best recipe for that). However, you can visualize how this full structure would help to slow down the tropospheric-portion somewhat"

Thanks Isotherm! It certainly appears that we are firmly on the road you are forecasting strat-wise. More amd more signs, and stronger indications as well ,that the progged events, Wave 1 and 2, indicated several weeks ago are only increasiing in forecasted outcomes as we get closer in time. Many people feel that the incorrect SPV displacement could yield the coldest and snowiest sensible weather towards Europe and Eurasa. As seen this AM on MichaelVentrice's Twitter feed. From your previous reply below , in regards to displacements , you indicated that displacement favors North America. Yet, I still hear some folks stating the opposite. I imagine there might be confusion over a tilted , or partial displacemrnt versus a SPV displaced completely away from the NA continent. ( As mentioned below ) I will be closely following to see how things play out, very fascinating stuff going on right now.

Excellent update Isotherm ! Things are progressing well for December so far based on your initial seasonal forecast. Just a quick question, I hear some strat expert talking about the continued assault on the PV from wave 1 and wave 2. And how if history repeats itself based on studies the current precursor pattern might really weaken and displace PV soon. My question is, do you foresee a possible SWE taking place as well ? And if so, what implications would that have on your seasoinal forecast ? Bear in mind I know we are not dependent on a SWE for the sensible weather progression you have forecasted. Alas, I find the mention of this possibility interesting. I hear TonyWells@scotlandwx talking about a possible SWE at the end of December, and I also hear HM mentioning that if the PV weakens, as he thinks it, it could open the door to some very nasty winter weather at the end of December here. Thanks Isotherm.

Great update Isotherm, makes a lot of sense! And maybe your progression could lead to a snowy period around the holidays as we come up towards the later part of the month.

Thanks Isotherm!

Isotherm, great update, thanks ! If I may ask a quick question, recent modeling in the last 24 hours, ie., EPS and even the GEFS , also the Euro weeklies, have some folks concerned about December as a whole, ( warm vs cold ) with weakening of the -EPO and changes over Alaska. Is this to be expected and it seems that the models have been having a hard time recently. So, I guess what I am asking is don't worry about the models ? The colder/ snowier second half of December is still a outcome to consider ?

Thanks

A question please, do minor changes here have a lag effect to the winter ? ( I know sometimes SST patterns change in the Pac, etc., but to have an immediate impact on the atmosphere may take months I think from what I read here ) So with that in mind do you see anything dramatic on the horizon, or are we basically set with the Modaki from a winter outcome view point? Thanks

Of interest today I see the new UKMET seasonal was issued, and to my eyes it seems to have gone to more of a -NAO look very it's previous update. Seems to echo your forecast of the NAO to a degree. I wanted to say your NAO forecasts are remarkable, especially in view of how difficult, if not impossible that indice is to predict on a seaonal basis. I include this as well for reference :

Isotherm thank you for your outlook. I was looking forward to it . Can you explain, if time permits, why you feel a technical SSWE during the MET winter is not likely this year? I read this part " solar flux is running quite low, as we descend into the minimum of solar cycle 24 (which is still at least 1 year away). Flux values have generally hovered around 700 or slightly lower. Suppressed solar forcing in concert with increasingly westerly shear stress due to the positive QBO will act to stabilize the upper level stratospheric vortex, and destructively interfere with sudden stratospheric warming events." I thought maybe the odds were higher due to the phase change with the QBO and the low solar background state. Seems we need solar forcing ? Thanks, and much appreciated !

Would you then say weaker Nino = colder winter overall ? versus 02-03 and 09-10 possibly ? And maybe certain areas will simply have more snow ( above climo ) due to more frequent events, ( even with less -NAO ) versus years like 02-03 and 09-10 that had HECS / MECS and contributed so much to the overall snowfall totals. I still like the overall manner in which the SSTs seem to favor keeping the MJO out of the super warm phases. That could change though at some point.

Ray, what is the root cause of the moisture supression ? I thought last month a classic storm track was shown by the seasonals for the winter months. And the strange thing yesterday was the UKmet 's winter precip pattern too, at least to me, as I can't figure whether from moisture pattern was due to upstream blocking or what.

You expect the rise to continue with the SOI now negative? Also, any associations between the trending colder waters near the Phillipines and the NAO in the winter? I believe somewhere in this thread I read that either warmer or colder waters in this region has some sort of relationship with the upcoming winter NAO phase, maybe it was Raindancewx, not sure.

Wow, very quick and still rising. This is from the West Pac storms, is that correct ? Moderate in site maybe .

Agree.... in the end despite any changes to the El Nino, I think we are going to lack help in the my area, the Mid-Atlantic, from the NAO domain. However, maybe we counter that by having more nickel and dime events ( -EPO +PNA ) . If we get a period of - NAO and get cooperation from the Southern jet and disturbances , like in 09-10 then maybe one single storm we could put down a lot of the seasonal snowfall. However to based a seasonal forecast on that outcome is silly . I am looking forward to your outlook. When is is due, later this week ?

Speaking of the Pac and the El Nino , this might be of interest to you as HM was talking about how we get to a certain outcome(s ), starting from two different beginnings . Not putting words in HM's mouth but I thought this was a interesting post by him this morning. You can see below:

Ray, to me this adds further evidence to the coming El Niño and supports a continuation of warmth transport , at least from a ocean current origin, moving from the warmer waters of the far West Pac East to the Central Pac, and somewhat beyond. As Ventrice mentioned , "this is the longest fetch of surface Eastward currents I have seen to date to year. "

Weathafella, you might be correct. Interesting developments continue with this progressing El Nino ..... I really like this going forward in time.

Not good news . Might need to do sod now under the trees , or my wife will kill me .

You stil feel that the stronger the El Nino , granted it is West based / Modaki , the more it could benefit my region , the Mid Atlantic ? Also, have you done any research about the type of El Nino and the correlation the the NAO domain? Through the years so many NAO formulas by others have not worked out. However, I remember you mentioing Tom ( Isotherm) has fairly good skill in this area, looking forward to his thoughts as well as your Winter forecast later on.

Looking at that Euro forecast graph it would appear it takes off rather quickly from here, most of the forecasted rise is closer to the present versus later. Does that mean the forecast is more accurate, not sure. Ray, is that forecast bordering on moderate now ?

What, if any consequences does this have for high lattitide blocking in October and even beyond, in and around this region ? Also, recently looking at the SST changes in the Gulf Of Alaska they are rising . Would any of this warmth cause and or re-inforce a + PDO in developing in the month(s) ahead.