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Appreciate your posts PSU , I imagine it is a double edged sword to a degree, we'll get our opportunity hopefully between the 16 th and 25 th.

psu talked about this. I would not weigh too much into the MJO forecasts at this time. The blue color indicates a - NAM state, ie. HL blocking, and as mentioned here before, there is a tendency that even if the AO goes positive later in the month it will once again go negative , normally there are several cycles to this event on a time a scale going out to almost 60 days. Also worth mentioning, the real impacts of the SSWE is not due to hit sensible weather for 20 to 30 days after the official wind reversal. So, the models may adjust to colder longer term if our area is favored for the Southern displacement of colder anomalies. If this occurs hopefully a baroclinic zone sets up near by and we can reap the benefits of increased probabilities of snow over rain. I guess the bottom line is don't over react to model data in the long range, and set expectations within rational levels.

This looks good

Going where ?

Yep. Ah the old days of 2002 - 2003 I remember - 4 and -5 up there. An update from @Isotherm seems in order in regards to the SSWE. Here is his outlook for this month: January: z500 structure = neutral or +EPO/Near neutral AO/Near neutral or negative NAO/+PNA: this month, while still warmer than normal for most of the United States, will provide the highest opportunity for winter conditions in the coastal Northeast and Mid-Atlantic. Temperatures will be colder than normal across the Lakes and New England, near normal into the northern Mid-Atlantic, and warmer than normal elsewhere in the country. Snowfall will be above normal in the Lakes, New England, and near normal in the Mid-Atlantic.

Yes that is true, we have record North America snow cover the last two winters, not sure about the other side of the pole. However, keep in mind we went from record North America snow cover to dropping like crazy during Jan both of those years, I believe one was due to the SSWE and the other the Pac induced flow into Canada. I do know that Siberia set record high temps back in the summer and possible the Fall. Not sure of the consequence of that. Both of the past horrible winters, as you know, featured so so Pac patterns with little blocking in the NAO domain and I believe the AO averaged positive. The Pac effects the EPO region, PNA region and Canadian snow cover. It has HUGE implications for us. So far the - AO and the - NAO has done little this winter. Also, keep in mind the numerous model failures the last three years in bringing cold to our region. There is way more to it than that though.

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