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It is interesting to discuss the long range, but you should realize that modeling, in general, at long leads is perilous. The base state is a warm one so far this winter. Cold air masses are at best feeble. If it were not for our hobby's purpose and never ending quest for guidance and quest to discover the forecast beyond day 5 we would eliminate the never ending model chaos. I think I read recently the increase in social media sharing of models at exceptional long leads only causes further mind bending beliefs that we really know what may transpire. I tend to agree with that general idea. But, if you use the data wisely you can learn and move the science forward. Certainly modeling has improved the last few decades. On a more relevant long range note, a quick carry over post from snowy over at 33. Still some hope for later in Feb though ........ << There's been so so so many posts arguing about the MJO, but at the end of the day, if it doesn't get to the extratropics and the poles, it's impact is rather limited. Again it's going to be gradual. But a positive AAM is a positive sign. Nothing definitive and no sudden equations or conclusions to be made there, but is a hopeful sign. Cautiously optimistic is the best place to be IMO. >>

Would love @Isotherm 's take on this. I myself thought the pay off was the winter ahead , so 20-21, however, I am not sure, I also thought there was a multi-year - NAO lag after a solar min. Believe the projected min date is between March and May 2020. Some feel the association with deep winters ( colder winter and more snow ) and the solar min has been watered down and diminished due to a reduction in overall global sea ice .in the past 50 years. Just speculation there.

@psuhoffman hmm saw this and thought of your post yesterday

Something to think about , this does coincide with a period of reduced zonal winds. However ,based on what I am hearing and seeing a true official SSWE is not likely this winter. The vortex is resilient and strong. But as HM mentions, it does have a vacillation cycle near the 20th of the month.

The theme of the little things screwing us continues. Realistically with a look like that in Western Canada you would think the Atlantic might react better in the area near Greenland, instead look at that hot mess. The multi winter + NAO continues. I was reading about the dynamic models versus the statistical models in terms of the HL call for the winter . One model camp sure nailed it. Well, at least so far that is. I still have hope for February. The progression of sensible weather ,not necessarily how we got there, does seem to match Tom's progression nicely. If so, his ideas and the notion we pull back ridging in Feb and get an East Coast trough would spell opportunities for us. In this new day and age of non-analog winters and changing base states I would be happy with just a two week window of very cold and snowy weather. I don't even care if I don't hit average snowfall , give me 50 % of the season in two weeks with cold and wind and make it look like days of old . To me that is a win.

Great update from Don S . Here it is courtesy 33: << posted 24 minutes ago By now, the above normal height anomalies shown on the closing days of the operational ECMWF have likely gained notice. Those height anomalies and the accompanying temperature rebound are well-supported. The 12z GEFS is in good agreement with the 12z operational ECMWF at 240 hours. However, by the end of the GEFS run, the area of above normal height anomalies retrogrades toward western Canada and a trough takes shape in the East. My thinking has been and, at least for now, remains as noted in my nearly daily discussions of the longer-term pattern evolution: During the coming weekend, colder temperatures are likely. The temperature could even fall into the teens in New York City on Saturday morning. Afterward, even as moderation should follow for a time, the cold will likely return during the closing week of the month. At that point, the cold could become sustained and it could continue into at least the first week of February. Obviously, the situation bears watching. At least for me, I will need to see more evidence that the change is not a temporary period of moderation (highlighted above) during a transition toward a more sustained period of cold. The evolution of the teleconnections and progression of the MJO will provide insight over the next week. If people want something gloomy to consider, January 1-15, 1998 had a mean temperature of 43.3° (2020 was 42.7°) in New York City. February 1998 went on to have a mean temperature of 40.6°. If people want something more appealing to consider, January 1-15, 1907 had a mean temperature of 43.5°. February 1907 had a mean temperature of 25.9° and monthly snowfall of 21.8". >>

Similar to the issues last year at times. Little ROI in hobby land these days, as Bob did the right thing focusing on the cha ching. Maybe in Feb. we score as we hopefully progress to a more traditional Nino-ish pattern along with legitimate threats. If we hit a great two week snow period we can still make up for lost time.

Random thoughts ...... some may hit your question, others not , will also think more about this tonight. Temperature profile of the Atlantic might be one reason, effecting confluence and blocking.....changes have happened over the past couple decades in the Atlantic, maybe even the Gulf Stream. and changes up near Greenland too. Changes in the Pacific Ocean current and base state in the last 20 years - with an emphasis on the Western Warm pool . Favoring warmth phases over cool/cold - faster Pac jet, more warmth transport, higher moisture content. bluewave and others have posted and mentioned there has been some sort of change in normal snowfall distribution during the last 10 years. more snow in warmer periods. Reduction in Sea ice leading to changes in the EPO region . Slightly rising global temps Maybe the current global base state favors more higher impact , higher moisture events, but not as cold as decades ago due to the reason above. You get more warmer snowfalls, more dynamic snowfalls but less small scale REGIONAL snow events because cold air can't not maintain or counter the warmer push. Might even over lap into the global baroclinic zone and the wash out effect. You need dynamic systems to produce the snowfall anything less or weaker events are rain, unlike decades ago. Maybe these effects are more pronounced at lower latitudes as well, meaning our area and the area in your study. That might be a reason as well. Ha ha that is my wag.

We don't need extreme cold for the favored period as you mention. Maybe arctic air waits for late Feb , seriously. Wonder if we go to a typical Nino pattern in the later stages of the every two week pattern. If we can flood Canada with super frigid air in mid Feb and then deliver it via an improving NAM state maybe it is possible. The ridge pushing West during Feb fits the Nino progression as you mentioned as well. We know during early Feb and on we will have the active STJ . Another time period to note is one that also seems to be on a pattern, and I am referring to the PV vacillation cycle.....( in strong Vortex winters ) ...date of the 20th of the month , as HM posted days ago, ( see last two HM posts ) it has been going on near that date on a regular basis. Wonder if that ties into a significant event for us near Feb 18 th to the 22 nd.

Of note, bluewave mentioned this a while back, we have been lacking a Miller A track and even a Benchmark storm(s) in the winter recently . Folks have scored up North but in some unusual ways. The Pac jet the last two years, in varying ways, has interfered with some of our favored windows/threats for us here in the Northern Mid Atlantic, to what degree is debatable, and you can refer to climo, as it just being par for the course. Some years everything goes right, some not so much.

Whether this matters down the road is debatable , but there does seem to be some indication is a slowing of the zonal winds in the weeks ahead. Not sure how much of that is typical seasonal effects taking hold. ( weakening ) Any one know when the new QBO data arrives ?

Excellent points, goes along what I was thinking about change in general, no one pattern has legs.

A very intense wave breaking cyclonic event next week, wonder the implications for the time period afterwards. Very complex to figure this one out for us.

If we can get some cold air masses to be present during early Feb, we will have an active STJ to work with. However, I can see a lot of ways to lose. Cold air seems to lose out the closer we get to any events so far this season , and sometimes the Pac jet interferes with Western ridging. But, there is potential, which is better than 70 and sunny on Groundhog's Day.

This November's head fake, just like November 2018, was alluring and drew some folks in . The seasonal models so far are nailing this winter. Too bad they sucked last winter in predicting the epic pattern that did a Pamela Anderson. Bravo so far to Isotherm. Modeling in the long range this year seems no better than last year in losing favorable patterns. Whether it means the little things that are causing it or larger scale issues, what matters to me is that you can not put any faith in solutions beyond day 6. I know our regional climo sucks for snowfall, but you have to see that there have been some rather large scale busts in patterns in the medium range since November , with incredible swings in the EPS and the GFS.

Interesting post ,but what are your thoughts here in regards to using Februaries with AAM > 2.0 per as BAMWX just did as means to forecast warmth in the East for this coming Feb. Would you say unreliable because they are focusing on just one thing?

The close up is is rated XXX

Latest from Don S about an hour ago. I enjoy his updates for our area in regards to the information he presents on the MJO sand the AO. Here is Don's post: <<<< Today again saw temperatures run above normal. In the Southeast, near record and record warmth prevailed. However, the prevalent pattern that saw New York City record a mean temperature of 42.7° during January 1-15 (6th warmest on record going back to 1869) is coming to a close. Winter has not been canceled. During the coming weekend, colder temperatures are likely. The temperature could even fall into the teens in New York City on Saturday morning. Afterward, even as moderation should follow for a time, the cold will likely return during the closing week of the month. At that point, the cold could become sustained and it could continue into at least the first week of February. 　 In addition, on Friday night and Saturday a system could bring New York City and Newark its first measurable snowfall since January 6. Philadelphia could receive its first measurable snowfall since December 11. 　 Initial snowfall estimates are: 　 Albany: 3"-6" Binghamton: 3"-6" Boston: 2"-4" Bridgeport: 1"-3" Islip: 2" or less New York City: 1"-3" Newark: 1"-3" Philadelphia: 1"-3" Poughkeepsie: 3"-6" Scranton: 3"-6" 　 The ENSO Region 1+2 anomaly was +0.2°C and the Region 3.4 anomaly was +0.5°C for the week centered around January 8. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.27°C and the ENSO Region 3.4 anomaly has averaged +0.50°C. The remainder of winter 2019-2020 will likely feature neutral-warm to weak El Niño conditions. 　 The SOI was -11.63 today. 　 Today, the preliminary Arctic Oscillation (AO) figure was +3.622. 　 The AO had a preliminary average of +3.560 during the January 1-15 period. Since 1950, there were 7 cases when the AO averaged +2.000 or above during that period. Four (57%) saw the AO average for the final 15 days of January average 1.500 or more sigma lower than the January 1-15 figure (1952, 1983, 2005, and 2007) with 1952 and 2005 having a negative average for the latter period. All four had a negative AO average for February. Three (43%) saw smaller declines (1975, 1989, and 1993). All three had February AO averages > 0.000. 　 No significant stratospheric warming event appears likely through January 23. Wave 2 activity will remain relatively suppressed. Overall, most of the stratosphere is forecast to remain cold on the EPS. 　 On January 14, the MJO was in Phase 5 at an amplitude of 3.258 (RMM). The January 13-adjusted amplitude was 3.554. 　 Since 1974, there were 8 prior cases where the MJO reached Phase 4 at an amplitude of 1.500 or above in the January 5-20 period. In 7 or 88% of those cases, the MJO progressed into Phases 7 and 8. Progression consistent with the historical experience would increase prospects for the development of a colder pattern during late January, which could continue into at least the start of February. 　 Further, the MJO was in Phase 4 at an amplitude of 2.273 on January 7 with an AO of +4.048. Since 1974, there were three January cases when the MJO was in Phase 4 at an amplitude of 2.000 or above and an AO of +3.000 or above. In all three cases the Week 3-4 period was colder than the Week 1-2 period (smallest change: 2.7° in 1993; largest change 16.8° in 2007). The change in 14-day average temperatures from the above three cases would imply a January 22-February 3 mean temperature of 10°-12° below the January 8-21 mean temperature in New York City. This data implies that the latter two week period would be colder than normal overall. 　 In addition, an MJO in Phase 7 at an amplitude of 2.000 or above typically sees measurable snowfall consistent with overall January 16-31 climatology. That would imply approximately 2 measurable snow events for Philadelphia to New York City and 2-3 such events for Boston during the closing two weeks of January. The first such event should occur this coming weekend. 　 Based on sensitivity analysis applied to the latest guidance, New York City has an implied 84% probability of a warmer than normal January. The monthly mean temperature could finish near 36.0° in New York City. 　 Finally, the latest C3S multi-system forecast suggests that the February-April temperature will likely be somewhat warmer than normal for the region (despite what could be a colder than normal February) and warmer to perhaps much warmer than normal in Europe where winter has been largely absent. >>>>>

Some humor is what I needed . LOL

I need to study about the - MVP, first I heard about this. Another wrinkle in my expectations. Not enough time in the day. So much data. Maybe Bob or psu know.

So, Feb = highest climo snow potential around these parts, and maybe a more pronounced Nino response is on the way. Get lucky with some fresh arctic air, any maybe we enter a period of multiple threats during our best month. There was a recent post today over in the NYC forum about increasing AAM and how it can reduce the tendency for a - EPO / -NAO. However, Don S chimed and brought over some neat stats regarding that connection. @donsutherland1 also stated the post about increasing AAM doesn't accurately depict the relationship between AAM , the EPO and the Nino state. You can check that post out yourself in the Jan discussion thread over on the NYC thread. Don always manages to find some cool weather statistics on just about every weather element, driver and indices.

This will be interesting to track. Maybe winter 20-21 with a weak Nino , a well established -QBO along with a 12 month solar lag. LOL

The EPO is so annoying. Must be driving certain energy mets crazy......you know who you are.

You must be a great teacher ! Well done, and thank you psu ! Love the numbered system And yes, it certainly does help explain things.

No one is perfect, and I hardly ever post cranky's stuff , but we will see. Sounds to me he is expecting some re-alignment in the NH with the weather features, and then some sort of winter pattern emerging, aka. deep winter. Hmm