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Today's GEPS looks better.

According to Eric Webb courtesy 33andrain he states this : "The GEFS & EPS couldn't be more different after 300 hours in the North Pacific & North America. Subtle changes in the North Pacific storm track are mostly to blame as the GEPS which shows basically the same MJO forecast as the GEFS but produces a more similar height configuration to the EPS." Meanwhile some interesting thoughts by Webb and Paul Roundy regarding the GEPS and the GEFS.

@psuhoffman to go along with your previous post, note that NH snow cover has really declined. I propose 2020 has no analog currently, but what is clear is a continuation of the November head fake> Using November as a whole, and December prior to the 15 th as clues to help to forecast the true heart of winter, so far at least has been diminished the last two years. Snow cover looked great , now look at it and the extent. Yuck NAM looked good and now horrible. Very cold and anomalous November cold and now warm in may NH areas. What once worked as clues to the winter do not seem to carry the same weight as they did before the last couple years. I looked at the Northern Hemisphere temps and it is a bit concerning that is warm everywhere.

This from October 2019 , so basically 3 months have passed , note all 4 models indicate +NAO for the period DJF. Guess what so anfar it is correct. I believe HM a couple months ago thought there would indeed be intervals of at least some -NAO., so far nada... I would guess if we get one maybe it would be March. Would it be beneficial is hard to say, unless it falls into the mold of 2018.

Within the realm of random chaos I wonder if we do get an unexpected and sudden pattern change, because that is what the Euro Seasonal implies or do we stay the course discussed by psu because the players are stable. Even though psu did mention there are various options on the table. Some who follow the strat and the HL would think improvement arrives but the process is a very slow one.

Hope the EPS has a clue, because other modeling is not so great, and any improvement towards fantasy land seems to reverse course and goes back to crap. Remarkable consensus on a + 4 or even higher AO soon . And a forever - PNA as far as the eye can see. So then, with Jan written off, next up is Feb. There was a post Webb made over in 33 yesterday describing a blend of several good winters centered on Feb. that I believe he is associating with the Feb Euro seasonal. I am fine with his ideas but we need to see some changes to show up soon if that were going to be the outcome. As for the PNA ..... some thought we have a +PNA average during Jan and Feb, but not looking good at all. I can't overstate how important I feel having some sort of +PNA and or - AO is to our region. From Don S. - here is a segment of his update regarding some PNA stats : < Despite 500 mb differences in the extended range, there remains strong consensus between the EPS and GEFS that the PNA will remain negative to strongly negative past mid-month. Such a scenario would lead to a continuation of a generally mild pattern beyond mid-month. Transient cold shots would be possible. A PNA- typically translates in warm anomalies in the Middle Atlantic region. For the January 16-31, 1981-2019 period, the mean temperature for New York City and Philadelphia was 32.2° and 32.1° respectively. When the PNA was negative, those values were 34.2° and 34.1° respectively. The coldest mean temperatures for PNA- periods occurred when the EPO and AO were both negative (New York City: 29.1° and Philadelphia: 28.9°). The warmest occurred when the EPO and AO were both positive (New York City: 37.9° and Philadelphia: 37.5°). >

To me having agreement on movement is a win. If there is going to be a future change in the NAM state for Feb it will have to start from somewhere. This follows along the lines of the Euro seasonal I believe issued on 1/1/20 - it showed below average 2 meter temps across a large portion of the country. The temp signature seems to align itself with a - EPO delivery. During the next couple weeks Western Canada will be very cold and this could set the stage for ample cold to dig South first across the Western US and then gradually move East. The estimated times periods for the -EPO and the -NAO that some spoke of being Jan for the -EPO delivery and Feb for the -NAO may potentially may simply have been pusehd back in time.I could almost speculate a deep -EPO in Feb and then the first real deep -NAO /Davis Straits NAO block of the new calendar year being in late Feb to early March. Fitting again some speculation on a colder and possibly snowier March this year. This would coincide with the tendency of later season blocking episodes ( as in some prior years this past decade ) and allows the QBO to further descend and have an impact on the sensible weather pattern here in the East, not to mention possible reshuffling in the West Pac.

Will have to monitor this, may have some merit to it .

From Isotherm over in the NYC forum.... find his point about MJO phase 8 = pattern change very interesting, while he replied to this comment from a member that stated the MJO is looking better at the end of the month. I certainly agree with Tom, many things are at play and a pattern change will need enough overall push/amplitude ,etc., to counter the well established issues so far this month and looking down the road as well. from Isotherm : Keep in mind, the phase 7-MJO response is still a warm one for the E US, although cold-air transport into the Plains increases. One would need continued propagation into phase 8 at amplitude for potential/putative pattern amelioration [and as discussed yesterday by Bluewave and I, propagation into 8 is not necessarily a guarantee of a significant pattern change, either -- many factors involved].

I agree , the secondary move up in the AO forecast is very concerning. Some members with a ( + 6 ) Standard deviation. The warm feedback loop is very consistent. At the same time the PNA is set to go significantly negative. ( - 2 SD ) Forget snow and cold until early Feb, possibly later......Jan is written off in my opinion.

I agree, any beneficial changes for us will take time and patience.

Looking to down under for some positive signs for our weather ........ subtle indications changes are going to start by mid to late month. A recent post by Paul Roundy I believe some new data on the IOD is set to release in two more days.

@poolz1 wondering whether right now and for the next 5 to 7 days we see the strongest winter pv. Temps very cold and zonal winds increasing but then, after day 10, things begin to change up top. Hopefully, in time we transition to a more favorable NAM state versus the current ugly + values.

In regards to what I meant , @psuhoffman did such a great job of replying I will stop here. You can see his post above. Thanks psu.

Those are wise words. Even though the Euro has the highest skill and verification numbers you have to consider , as you said, the overall pattern.

The progressive pattern and unfavorable indices argued against this. Another win for the AO / PNA guidance. Honestly I think I rather have the PNA + and have a neutral NAM state. I would not be surprised to see the follow up event go to a cutter. The cutter theme goes back to last winter as we all know.

@showmethesnow as you might have seen the 06Z EPS not agreeing with the OP. It have the primary to our NW although there are a few members with centers to our South and East. But the general cluster is Western PA and Western NY state. Maybe this will change to a degree with the afternoon run.

Rather frustrating if you ask me. Many weather pros and mets are frustrated as well. I know this has been brought up before, as a matter of fact I think Don S brought this up a couple days ago about the warming of the "warm pool "and the recent research which suggests the effects are promoting, high amplitude warm phases, over cold phases and the passage of the colder phase being faster versus the warm phases. For those of you who might state well what about earlier this Fall when we did spend more time in the colder phases, well I am talking about a longer period of time, and when that time periods occurs. To me the MJO favoring warmer phases also seems to be happening more so in the beginning of winter, as it did last year at this time. I am referring to the later part of December and in January. Another interesting observation comes form HM, he mentioned recently that the warming of the "warm pool "may be over time effecting the wave train over North America in the time period from November to the first half of January. ( The cool part here ,as you will read below, HM is proposing two effects - the first a early season cold delivery via the -EPO and then warming from a shift in OLR in the IO- Maritime. HM also mentioned that the poleward heat transport is most receptive in Autumn, and hence it sets off the wave train which at that time promotes a favored - EPO. ( Now HM did not mention this but I also think there is some November influence from the mentioned wave train and acting upon the early season Siberian High, descending NH snow cover, etc in developing a early -NAM state. - like this year ) HM mentions this really cool idea that by late December the annual cycle redistributes probabilities through the tropics and then heightens the strongest -OLR that are in the IO - Maritime. I believe HM has something here. Many of the words I used above are right form HM's feed so all credit to him. I guess now the question becomes do we move forward from this cycle to a new one late in January and through February. There are some indications we do, but to what degree in terms of favoring sustained cold and snow I am not sure. On a side note, there are some interesting trends this past decade regarding longer summers and sometimes late season blocking developing at the end of winters. The absence of sustained - NAO is one as well, the late December warm-ups is another. Here is the referencing post from HM that I focused on.

Seems to be following the CFSv2 - used for trends only of course. Possibly the current CFSv2 outlook is based on the modeling seeing colder outcomes late in the month. Trends.....

Yes, you and Anthony on the same page. Using the reliable AO and PNA indicators this was expected in my opinion. Sure, a small chance we could have worked into a failed period or set-up but the stats that Donald S and Wes posted a while ago are remarkable. I mentioned a few days ago that without a favorable AO or PNA the threats would dissipate, or degrade. Since then they have. We will have to wait until the NAM state changes, and that will be a while.

Thanks Don, great info as always ! As you and bluewave both mentioned it will be interesting to see whether the MJO has any effect down the road on the PV.

I prefer to simply use the AO as a guide to SECS events. Indices were not supportive. Of course, more to it than that, but a -AO is a money signal. And we all know the current NAM state.

@bluewave mentioned this possibility a week ago. Today @donsutherland1posted over at 33 that the IOD has indeed weakened even further . You can see here from the site http://www.bom.gov.au/climate/enso/iod_1.txt Would be great if Don could share his thoughts here. We are now below the threshold of a +IOD I believe. 20191125,20191201,1.14 20191202,20191208,0.86 20191209,20191215,0.82 0191216,20191222,0.56 20191223,20191229,0.31

That depiction is right along the time lines of @40/70 Benchmark, and @psuhoffman. The issues with the Pacific ridge and its location goes back to last winter. Nothing new to add. I don't care what others might say that there are differences elsewhere, that set-up is a HUGE issue and brings the SE and WAR to play. Combine that with a very +AO and a deeply -PNA and it is very frustrating. Maybe things progress later in the month, but I believe any change to better will be gradual and no one should except a sudden flip.

A wag that the NAO may be more conducive next year to negative phases, also we will be fully established with the QBO. I know Isotherm mentioned the NAO being more receptive to - phases after the solar min, target date 4/2020 . multi year SST lag to NAO domain would be two years. I also read from Isotherm we have an issue currently as well in regards to ozone concentration and the NAO domain. The context he mentioned it escapes me at the moment.