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I enjoyed this post vey much and put more faith into it than the "weaklies"

So much for their hot hand....................( well like they said - need a few more runs )

Who knows whether the EPS will be correct, however, just two days ago it had the East in a cold pattern at hour 240, but now after losing the -EPO we are above normal, as are most areas East of the Mississippi River. Not horrible temp-wise, but not a winter-like period. Someone here, forget who, mentioned he did not like seeing the ridge North of Hawaii. I agree, that messed things up last year, responsible partly for the fast Pac Jet, lack of West coast ridging and assisted the SE ridge to show up. Hopefully if it does come along, it is simply a transient feature. Decembers can be, and are typically are transitional months, asking modeling to pick up correct outcomes a month ahead is difficult. A progression to above normal in early December should be taken in stride after the recent cold spell. Whether it is a month long affair as some are saying is really a reach. I prefer to concentrate up to 7 days. It is fun to talk about the possible weather drivers and the pattern but getting stressed over model runs after day 7 is simply not healthy and takes away the fun of this hobby.

Hot Off The Press , maybe the precursor pattern is working .

That makes sense. So, maybe he ends correct on the apparent turn to milder, but the duration of any warm up is shortened. I know HM talked about cold at the end of December which matches your thoughts here. Along with the general talk lately about warm or mild Decembers bluewave was mentioning the turn of events in the Pac since 2013, and how the recent warmer early Fall seasons turn colder in November and then mild in December. Here the focus is on massive warming in Pac this decade, and sea ice melts during the recent summers etc. This makes a lot of sense. Seems we have new players as a consequence of a warming global state and they seem to really impact the period form October to December. know it effects the entire year, but to us here at this time of year you can see it and feel it. The effects of a warmer base state promote increased ice melt but also effect seasonal blocking with warmth in the Pac ( mostly the deep tropics ) effecting the MJO, EPO regions, Hadley cell , tropical forcing , snow cover, etc., even SSW and other weather phenomena. Then there is feedback on certain ocean locations in the form of anomalies, and these are players to a degree as well. Looking beyond day 7 is a real gamble these days. models struggle as do forecasters. But, I guess, in this new day and age you have to incorporate these new players on how you decide to forecast the weather in the long range.

A weather friendly webb, but not for flies

Just like last year, if correct. Then, as you mention the response, just like last December , especially post 12/20/19, was the growing SE ridge. You believe this is a feedback, or is the cause for the shift in ridging further away form the West coast of NA the location of the warmer water? ( Being located further away form the West Coast ) The warm waters are not close like they were in the winter of 2014-15 I believe. Granted ,we are not talking extreme warm waters off the West Coast / the warm blob, etc., but there is an anomaly of warmer waters North of the Hawaii ridge. Seems like the anomaly has been shifting West with time. Also of note, is the Pac Jet coming in fast on the West coast of Canada, again similar to last year, when NA snow cover took a big hit up there. Even though that loss came more so during mid December 2019 period.

Well, I will bring over one of Webb's post and you can check it out. Me doing so does not mean I endorse his thoughts, but more so because it is interesting. Of note is that the atmosphere is acting to a degree as it is a Nino. A weak Nino though. Webb also mentioned we are ahead of the typical Nino/seasonal progression. BAMMWX stated we are ahead in terms of the PV evolution, from their webinar. Webb specifically said " This winter appears to be well ahead of schedule vs the stereotypical backloaded NINO progression thus far but that doesn't take away from my idea that December will probably end up significantly milder than avg. I think we're more likely to get this party started in January instead of waiting til February this winter, especially if this wave 1 SSWE is successful." Here is Webb's post form 33 : << The MJO entering the "circle of death" does not automatically mean the tropical forcing signal automatically goes away, but I do think it will enter the COD before reaching phase 3 because of the NINO/+IOD. In grand scheme of things, it honestly doesn't matter in this instance whether the MJO goes into the COD or stays outside w/ amplitude the entire time, the end result will be largely the same in the extratropical northern hemisphere. The MJO enters the circle of death when multiple circulation signals act simultaneously, or the MJO interacts with a standing wave like the one over the Indian Ocean. Why? Because the MJO is an eastward propagating subseasonal wave in the tropics coupled to the extratropical circulation. When this normally eastward propagating wave becomes quasi-stationary/stops moving eastward, its amplitude on RMM phase diagrams like the one below decrease. However, this DOES NOT mean that the tropics are not having an huge impact on the mid-latitude wave pattern. If anything, the global impact from subseasonal Indian Ocean convection will be much larger than usual the next few weeks because it's being amplified by & constructively interfering w/ a standing wave. That's not something the RMM diagrams will tell you. >>>> @C.A.P.E. Webb did mention we benefit from the -NAO late month, by delaying or muting any tropical based warming .

The MJO depictions, and recent model trends support his notion, as does the typical warmer than average December Nino here in the East, but there is one difference . That difference is progression, and what may happen is a change to a more winter-like pattern occurring sooner, versus later in December, which indeed would be remarkable. Reading Webb's posts does indeed make him sound like an embittered snow weenie going to the dark side. As for the Nino talk he does, I have been reading his posts for several years, and I believe he does focus on the Pacific/tropical weather patterns. I think he knows his stuff.

Regardless, I put more weight on Isotherm's forecasts. And so far, with a recent update at 33, he states that everything is going according to his seasonal outlook. Granted , as he admits it is very early. If Tom's ideas regarding December were going to to verify look for the Pac to become hostile in future model runs ( it has started to a degree ), and look for mostly warm MJO phases that tend to last longer ( similar to last December ) counter to what has been happening so far, and counter as well to the impact of the +IOD. He continues to favor the second part of winter, which according to his seasonal outlook is later Feb into March. ( based on the QBO I believe and other factors ) . I have no idea how things are going to evolve. There are certain things that are positives that I see, while others are a red flag.

Yes, that is correct. Just putting it out there. You have to weigh all opinions.

That was a real killer last winter. It increased the Pac jet along with the reaction to pump the SE ridge. Also, prevented West coast ridging from holding on for more than a day or two. Again, one of the two schools of thought will be a winner soon. The warmer Decembers, 80 % of the calls, or the 20 % more normal or even slightly below Decembers. If the SPV holds on that is a win for Isotherm. If the seasonal models are correct with a lack of a -NAO and a -AO then BAMMWX better change their tune. Meanwhile maybe Webb will be correct, I mean after all, you can say what you want about December, but, there is no denying most Decembers from 2010 on have been warm. You have to take into account the new warmer base state. It is typical to have above normal Decembers in a Nino year. Taken a step further, as psu said and others, now-a-days Ninos do not deliver the same weather outcome as they did back in the 1960's. And yes, we do not currently have a robust Nino but are feeling the effects of typical Nino tropical forcing at times. We are coming off an extremely cold first half of November and may need some time to cycle back. Maybe late December is a timeline to look at. So much uncertainty and many folks did mention this winter would be the most difficult to pin down.

Well, this is interesting. Need a expert strat person to weigh in.

A quick look at the IOD and where we may be going. Currently there was a recent update regarding the IOD by the Australian Meteorological service Briefly, it is forecasted to lag its normal weakening progression. What this means it could retain its powerful influence as a weather driver into the end of the year and even longer. It is still at very high + levels currently, even though it declined just a bit. Weekly Tropical Climate Note 12 November 2019Next issue19 November 2019 Slight weakening of positive Indian Ocean Dipole The positive Indian Ocean Dipole (IOD) weakened marginally during the past week. This is likely due to interference with the Madden–Julian Oscillation as it moved over the eastern Indian Ocean and therefore unlikely to be an indication of the imminent decay of the positive IOD. The most recent weekly value of the IOD index was +1.7 °C, down from +2.0 °C the previous week. The threshold for a positive IOD is a sustained value of +0.4 °C or greater, so the current event remains strong. The influence of the positive IOD is reflected in the latest rainfall outlook issued by the Bureau, which indicates a high likelihood of below-average rainfall for much of northern Australia for the remainder of November and throughout December. The positive IOD is also likely to lead to a delay in the onset of the Australian monsoon in 2019-20. Climate models surveyed by the Bureau indicate the positive IOD is so strong that its breakdown is likely to take longer than usual. The decay of the IOD is associated with the seasonal development of a monsoon trough in the southern hemisphere around December, but this process is well behind its typical schedule and is likely to happen significantly later than usual in 2019. As a result, the influence of the IOD is expected to persist into January 2020. Great educational video

My mom, when she was alive, would always talk about that snowstorm. I believe she mentioned thunder and lightening with it. We were on our way to Christmas eve services.

Did you mention as well we see a break then in Jan and Feb with March be snowy? ( Or was that just pertaining to a analog year you were referencing ? Sorry, I read all your posts, but there are so many great ones with various analogs I get a bit confused. :-)

Are you still liking the possibility of snow near Christmas? Some of your analogs were very interesting.

Good point, some mets point to the previous warm blob as an outcome of the pattern in place, and not a pattern driver. However, I do believe the record + IOD is a huge driver this year, and it is effecting the MJO phases, progression and timing.

@Ralph Wiggum believe you were interested in this possibly, The area of the Chukchi Sea is still far behind other years in terms of icing over. There is even research on this area and when the onset of the freeze will begin. According to the source we are very, very late. 28 to 41 days later than the long-term mean ( 1981-2016 ). If this is a driver to the pattern based on the delay in ice onset it should continue to be driver for at least the next 1 to 2 months. Projected Onset of Freeze on the Chukchi Sea Continental Shelf in 2019 The purpose of this experiment is to a) develop an informed basis for advising a hypothetical maritime interest operating in the region; and b) to identify conditions that cause sudden large departures (increase in risk). It also provides a result that can be evaluated against other methodologies. Projection: Freeze onset on the Chukchi Sea continental shelf northwest of Icy Cape is estimated to begin between 23 November and 6 December 2019 (Fig. 1). This is 28-41 days later than the long-term mean (1981-2016). The onset metric is defined by sea-ice concentration reaching 30% as determined by passive microwave observation in the reference area shown in Fig. 2 (top). Fig. 1. Observed day of year that sea-ice concentration in the reference area northwest of Icy Cape first reaches 30%, as determined from passive microwave data. The blue markers show the range (14 days) of the projected onset of freeze in 2019. The dashed line shows the long-term mean (1981-2016). Data considered: 2016, 2017, 2018 and 2019 in-situ observations from autonomous ocean profiling floats, aircraft and satellite-derived visible imagery, and SST radiometry. Persistence is evaluated using historical ice concentration data from passive microwave satellites, provided by the National Snow and Ice Data Center (NSIDC). Rationale: Data from autonomous floats indicate upper water column (5-15 m) temperatures in the Chukchi Sea in 2019 were as warm as 2018 between Cape Lisburne and Icy Cape, and considerably warmer than 2016 and 2017. However, in 2019 the water column was more stratified than 2018, and bottom-layer temperatures were cooler. Moreover, float observations show that a relatively thick, cold (-0.8 to -1.6 °C) layer of remnant winter water persisted into autumn near the shelf break to the westward of Barrow Canyon. Thus, it is likely that the water column on the northern shelf will cool faster through mixing than in 2018, offsetting the presence of a very warm, but thinner, surface mixed layer (Fig 2 bottom). Fig. 2. (Left) Map showing the reference area northwest of Icy Cape (red box) adopted for this projection. (Bottom) Temperature plot from ALAMO float 9234, initially deployed in May 2019. These data show that cold saltier water (generally -1°C or colder, ~32-32.25 PSU) persisted on the Chukchi continental shelf through the summer, under a relatively thin surface mixed layer. Plots of additional variables from this and other floats are available at https://www.pmel.noaa.gov/arctic-heat/. Review of historical data show that freeze-up has been uniformly later than the long-term mean since 2002, and year-to-year variability has been less. This is due in part to the consistent minima in Arctic sea-ice extent leading to a decline in 2nd year ice advection into the reference area in October and November. The greater distance to the summer sea-ice edge in 2019, along with above freezing water temperatures seen in all of the float data from Canada Basin down to ~100 m suggests that ice advection will be less of a factor than it was in 2018. At freeze-up in 2019, it is likely sea-ice in the reference area will consist entirely of thin, newly formed types (e.g., sheets of young ice and pancake), especially near the coast.

You hit the climo part, which is my main concern. However, looking at the glass half full , maybe winter is showing its hand and we will revisit this favorable pattern again later in December and in early Jan. when we reshuffle. I like the pattern to produce a significant event in the time frame you have spoken about. A very interesting - NAO on the EPS, Webb and HM both alluded to this a couple weeks ago. Sure, it still has to happen, but it appears more likely now. So watch for the HA event near the NAO fluctuations as Bob spoke about. Also, a quick look at Ventrice and his wave 5 portrayal

Still, a pretty crazy look at 500.

I am not so sure about cutter, and even if correct I am happier to see the cold. When I magnified the image up I could speculate maybe a clipper pattern. The immediate Middle Atlantic and SE coast is interesting. I wouldn't worry about that too much. Heck, I am not even sure how well the JAMSTEC does . To me just a piece of data.

How good is the JAMSTEC?

In that same post they mentioned this :

This was touched on yesterday a bit, but the thing is the Euro is not backing down on the +NAO call at all. And, yes, it could be correct . And then again, persistence does not mean it is correct either.