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Here you can make your own conclusions, but you can clearly see the impact of the jet stream , weekly mean ( wind speeds at 250 hPa ) and notice how it is oriented /magnitude early in 2019 and at the end of 2019.

Here is the decent GloSea 5 data showing the next 45 days of zonal winds. Bottom line is the vortex does not weaken, and hence most likely the NAM state remains unfavorable during Feb. and even March. Certainly no SSWE this winter. If you look at some models in the medium range you will see a dip in zonal winds but then they come back up. As stated previously this season, the vortex is very resilient and recovers after attempts to weaken it. Either timing was off in wave 1 and 2 attempts or simply the delivery was not efficient. Bravo @Isotherm

@psuhoffman awesome stuff if the research and conclusions are correct.

@psuhoffman not sure you track this but this is interesting. The Euro monthly now includes zonal winds at 60 and 10

aka Just another Midwest snowstorm. Honestly, think about it , is there any indication that this winter's base state and indices really support this idea he has? I don't need GFS snow maps, probabilities map, EPS mean snowfall mean, MJO etc., all I need is to simply look the AO and the PNA domains, and they say no to snow. ( Don S research and stats back this up ) As mentioned a month ago, when these indices become favorable that is when we score a significant event, until then, more of the same. More cutters, more transitional weather. More mild than cold.

This is pretty cool.

Hopefully in a week and past Eastern Canada will be colder . Again ,take these deviations to heart as to what they mean, and yes Canada is cold, however what I am looking for, and hoping for, is getting a colder air mass to develop to our North in early to mid Feb and then to move South into our region.

There are some potential reasons, as discussed last week, that March may deliver this year. I would not be surprised in the least to see snow totals in March greater than December 1 st to Feb 29th in our region "if " we do not score in Feb with a significant event of 6 inches or more. Yeah, that is not saying much , but if March were to deliver it might lend a little ammo to the belief winter starts later and either ends later or gets invigorated later in the season. ie late season blocking I don't see a March 2018 at this time. But, you never know. Why would an anomalous Davis Straights block develop, but I leave the door open. But March seems a good period as some mentioned this in seasonal forecasts. It is certainly possible the EPO stays neutral or positive through March and the AO stays neutral to positive as well. But, like you mentioned psu some things do give some hope that this March may have a favorable period. If by mid Feb we see the NAM state begin to change in our favor, and if Canada is very cold, that might be a clue that March can deliver. If the NAM remains neutral than the cold is locked up t our North with the continuation of the fast progressive /cutter flow and at most short intervals of cooler air in a slightly above temp. regime. Just some speculation.

Most here know this already but still..................

Pretty sad when you look out from our region. The Southern portions of Canada and most of the US in general equal very little snow.

I also read the fast flow across thousands of miles of the NH will decrease model accuracy. So be aware that all solutions in the medium, and long range especially, will have have some significant swings and changes. Only making the active periods even more prone to model chaos.

I really hope the later season IOD influence is cold as it should be, not some nutty new thing.

@Ji keep an eye on early Feb., just as a period of interest , goes along with Simon Lee's post and HM's as well.

There have been times this winter, more so back in November and December where the vortex can become more prone to displacement events and elongations. Folks will look at the 10 hP winds GPH for clues as to what may happen down the road. During these times our weather was effected with cold intrusions. The animation above was focused more so on a possible split, but note the orientation as well, it becomes stretched and elongated and almost splits at 10 hP. But, there is more to it than that, as the animation only focused on 10 hP. But, yes, it can effect our weather is the short answer. But it would take pages to explain the various effects from each type of event and to cover both the SPV and the TPV, including coupling , top up event and a bottoms up event , and the geographic target zones of where each event is most likely to impact. Some events favor the impacts targeting Eurasia, others Europe and some the Eastern US.

I know Bob and psu commented about HM recently struggling with the pattern , but I enjoyed reading Anthony's latest series of posts just now about the "potential " period of interest as it relates to the vortex, wave driving and maybe some pressure going forward. I suggest you check it out. Very interesting series of events in early Feb, but the timing could coincide better as HM mentions to the vacillation period that we have seen the past few months in a row between the 15 th and the 20th versus early in Feb.

For the love of God, just once have this come true. I always say you have to have big digital snows show up fist and then have a Southward placement of them to feel there may be potential down the road. Total speculation, but if the EPS were to start gaining members and the numbers increase overall I say this period has merit. On a side note, there also seems to be some connection at this time from a pv elongation.

The robust Pac jet is causing issues yet again, similar to other times this winter, and last winter as well. Still way out in time though.

I will believe post verification, but maybe there is an interval near the to, or prior to the weekend event, that the NAO actually goes negative. We can talk about block location versus the value, but at least the Atlantic looks interesting to a degree. Whether it plays a role in the outcome not sure.

Nothing like consensus, and shame on me for even looking at a product such at this, but still it is amusing.

The accuracy and verification of the icon is ....... seriously I think it is not terrible but not in the same league as the better models. When was the last time is had a win over over models?

The mother of all backlash snows for my area was the 96 event. Hours passed after the primary passed to my East without snow falling, but as the upper energy dived into the system the backlash developed and really hit areas further West and SW. Isolated pockets of 30 inches of snow, really incredible. I also remember this storm because it was seen well in advance but while the American models had it more a Southern Storm, more so DC the Euro went for a larger system and extending more NE to effect a larger area. Accu weather at the time in Philly, through channel 6 ABC, were honking on a Wednesday for the following weekend that a major Nor Easter Snowstorm would effect the area. ( with a high degree of confidence ) This is when the reputation of the Euro rose to recognition I believe. The tag team ETA and the Euro at the time were both talked about a lot by Accu Weather and KYW News radio who at the time had Joel Myers and Elliot Abrams doing play by play on the event. I loved that storm. Awesome track and the perfect set up.

True, and I respect HM as well. However, you are correct, HM has struggled in so much that his various calls on certain events have occurred, ( precursor events, and signals etc. ) however, the intended impacts have not manifested into - NAO cycles and deep - EPO periods, or a weakening vortex, etc. I admire his work and his track record is still very good. His call for the -EPO period in which we could experience a 4 to 6 week spell of real winter- like cold never materialized so far, and may not unless we see a dramatic change soon. Everyone, except for a couple folks, have struggled this winter so far. The only one that comes to mind whom predicted less snow and warmer temps along with a averaged + NAO and little blocking in the HL has been Isotherm. He has been stellar so far this winter. His insights as previously discussed earlier this week has guided his seasonal forecast well so far. Whomever can forecast the long range correctly a majority of the time deserves huge kudos and monetary rewards. It is the most difficult and challenging aspect in weather forecasting I feel. The changing drivers and evolving base states are re-creating the useful data used to guide seasonal forecasting, causing a diminishing of previously used weather analogs and methods in my opinion.

If you want to focus in on a period of interest in regards to the vortex then look to Feb 1 st to Feb 5 th This period is where the heat flux starts to move poleward. These have been rare this season so far. Will it be enough, tune in during early Feb to see what transpires.

Anything hopeful I will take. This does fit the time period down the road in which the vortex may start to weaken, and the calls for a - NAO to set in towards later Feb and early March. We can only hope at this point.

Good points. I can certainly see a record low snowfall total for this winter season. Tracking lately has no real inner-fulfillment. The STJ showed up, but meaningless, in a base state of zero cold air, no blocking, cutters, progressive systems, etc. If we don't score in the 10 day window or late in Feb or March snow totals in the Coastal Plain and in my area as well might be just a trace to an inch.