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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.

Thanks psu. Anything would be better than the 3 predominant storm tracks we had last winter. Over and over again, it got taxing.

HM reinforcing what many of us here know already, times are a changing in terms of using historical analogs to help with seasonal forecasting. You really need to be creative and do your homework. Recent years only prove this more and more in my opinion.

I can tell you one thing the orientation of snowfall anomalies seem to be lining up a bit differently this late Fall versus last Fall. Totally speculative. I know the Euro Control run is wild beast but you know looking at it last Winter it did depict future snowfall in terms regions rather well. No one should ever put any faith into the 46 day snowfall totals regardless of the model. Maybe the lower latitudes score more than Maine this winter.

Agreed. Looking at December with interest to see the validity of whether the recently record high +PMM actually does influence the STJ.

Hey psu what do you think abut the 06z GEFS? Some models put a trough in the SW and cut back on the West Coast ridging. You feel anything there is transient or simply the models are not getting it correct? Maybe a simple case of a relax, and then a reload. Some features at the HL are persistent and encouraging. Nothing really bad to say. And the things I am referring to are in la la land anyway. But, still interesting to attempt to figure out what is going on and thier implications for the base state as we enter December.

I see a lot of blue positives on that map. Funny thing is maybe we don't lose a ton of NA snow cover this coming December like last year. That in itself ups the ante for future arctic outbreaks here.

BAMMWX energy clients following their advice must be very happy. Potential for some traders to make big bucks if the real deal does go down. Not sure what the short positions currently are in the NG market. There goes the tropical analogs

Do you have any research or memory to support how well the GEFS , the Euro and the regular GFS does with strat forecasts ? ( or how well against each other ) I recall at times the GEFS does very well. I also read that the GloSea model ( from Euro I think ) has had a coup from time to time. I ask because I came across this morning two interesting posts. Goes along with my post above. You may even be aware of this already.