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True , and hopefully the PNA/EPO ridge develops as modeled.

Certainly seems post 2015 that a Greenland block and a - AO will not produce for us like they did years ago. There are exceptions though. In my opinion it has to do with the warming arctic summers and a slow to develop NH snow cover, that we need to induce the build-up of very cold air that we can tap into to. Also, a delivery method is need to get that very cold air into the East. The last several winter the Northern Plains have been very cold. I feel to get colder weather to the East we really need a very cooperative Pac. I profess that is more important now than ever. The elusive - EPO which has been a model forecast bust for the past 3 years never gets to real time. A Best pattern since xxxx has failed now several times this year and the end of December as well. Bluewave made a post that I brought over but you can see that the Pac really needs to be the prime driver for cold and snow in my opinion. I am no expert but just sharing some thoughts, It simply feels that drivers that would typically produce a SECS , fail to deliver for us on a greater frequency. Of course, the caveat is, we have a Nina and right there you know there will be challenges. Here is bluewave's post below: I am just calling it a window of opportunity for snow starting around the 16-18th. But it’s uncertain how much of the potential gets realized. The EPS is weakening the PNA faster now than just a few days ago. New run Old run

This still looks poor. The Pac puke has left its mark in Canada. I know some are expecting a change here by mid month, we shall see.

Are you feeling our window has narrowed down a bit? Its looks like it can produce near the 20 to 23 rd , but the longevity of it seems to be lessening. We kind of knew the Pac would improve, but then go the other way again. Certainly possible we warm up in early Feb only to turn colder again later. If indeed this SSWe has any role in our sensible weather it would produce another period of - NAM later in Feb.

It's possible we get little to zero snowfall , it has been mentioned above if a negative 4 standard deviation Arctic oscillation cannot deliver snow to the DC area then just forget about it , come back next year. Or, after the comet hits.

The GFS has issues we know, but many times it is very good at identifying large-scale features many days ahead , even 15 days ahead. I would feel confident about the prospects down the road and later January

Well why not. Shoulder month , fits the bill.

Dripping paint analogy from 04. I believe this is what the image shows. Not sure .

March might be nasty this year. If you are one whom believes the -NAM state lingers. @SimonLeeWx The most important aspect of a major SSW is the long, subseasonal persistence of the negative NAM/weakened vortex in the lower-stratosphere. This raises the likelihood of a neg tropospheric NAM & mid-latitude coldwaves across this timescale. For example, the 2004 SSW: 10:19 AM · Jan 7, 2021

Cold bias eliminated But I thought it was doing better.

Is it safe to assume that beyond this period , when the block relaxes the odds of a more significant all snow event increases for the northern Mid-Atlantic region?

@CAPE @psuhoffman Can you share your thoughts about this look in fantasy land. Is this a Mantiboa Mauler pattern ?

Didn't we have that last year or the year before? Good idea.

I believe there is a lot to be hopeful for despite the patience and wait that has been casted over the Eastern snow lovers. I just hope we here in the low lands get buried too. You are are in a great spot. Now the question really begs how long does the threat periods last. The stuff up above seems to indicate possible longer than many think. Hey while on the topic, looks like almost a split at lower levels and situated over Hudson Bay. Looking for cold, but also threats.

Latest 10hPa 60 N Notice the secondary descent

Secondary warming event seems possible, the recent upward swing in the AO may be short lived . Liking the possibilities later in the month as you mentioned for our areas. Hopefully, either an increased baroclinic zone sets up further South with any manner of threats, over running, West to East storms under the block with arctic air in place, and even a clipper like system.

Hmmm

Will the Miller B set up the third storm , for our area ? Thoughts ?

Noise is a good word. @antmasiello There is a reason I've been hesitant this year to call things well in advance. When all the polar heights are retracted to one side of the NH and baroclinicity is poor (relative speaking), it becomes like a sickly free-for-all of waves in slow/choppy flow. Noisy

35 day GEFS appears to indicate the vortex regains traction, some experts state any secondary warming may unfold. Also HM states the split was interrupted .

Accu Weather headline plus CWG may be incorrect to a degree, an official warming , yes, but a split not so sure. https://www.washingtonpost.com/weather/2021/01/05/polar-vortex-split-cold-snow/ Capital Weather Gang The polar vortex is splitting in two, which may lead to weeks of wild winter weather A sudden stratospheric warming event has pushed the polar vortex off the North Pole, sending Arctic air on the move See here : I am suggesting that we may never really get a split. Stratobserve was showing a very nice split , distinct and such, but now the vortex remains in one piece , seems to be a displacement event, but hey I am no expert. You can see here. 240 hours 300 hours 384 hours

That is true, most events don't benefit us. However, it can weaken and perturb the vortex, a plus, but then the question becomes does it ruin or side track a pattern destined to be good ala 2018 possible, but sometimes they ( warmings ) do benefit the East. Already there is much hype on Accuu - Weather , CWG, private services. The official warming was Jan 5 th , so add 20 days = Jan 25 th to see the cold materialize as per HM.

Canadian 10 day temp mean looks meh...... I know Canada is cold by our standards, but if you are expecting those really cold temps to magically drop South that modeling shows, well we have a ways to go in my opinion, because the 10 day mean does not support the look of " really Cold invasions of the past into the Mid Atlantic". Could be wrong of course, but this look does not look great.

@psuhoffman Psu Interestig comments by Anthony here wondering what to make of it. If forcing shifts later in the month of January especially with the latest forecast that show cold over the Eastern United States do you care to elaborate on what your feelings are regarding the progression of forcing in the West Pac. @antmasiello Replying to @webberweather I've been thinking about preseason/years like 88-89 showing up. Then I see the pattern ahead, etc. & tropical forcing reorganizing to Maritimes for Feb. You have to wonder if we see a rapid flip to very cold in W-C US. This would be a lot easier if polar state was more 1980s like 8:44 AM · Jan 5, 2021·Twitter for Android

Ed was on this first, now Accu- weather and others going crazy. Time will tell. Ed O'Toole @chionomaniac So things have happened quicker than I expected. Was also expecting minimal westerly flush down but this is greater than expected. When this is complete I expect another trop blocking response. Keeping an eye on possible split to reinforce this.