frd

Prior to this time frame with have this event unfolding below, note the vortex taking on a peanut shape (mentioned by Hugo a few days ago ) , not really a true split , as the depiction is at 50 mb, however ,as noted by HM, very important and not so usual. Cool things are a happening ........

GEFS does have some hits for our area on 12/21. I doubt this cuts. Either it hits, or a Southern slider or OTS. Damn, that block, so pretty !

If I recall correctly last December was for the most part was dry. I remember not having any issues with my "Longwood Gardens -ish " type Christmas lights out front. This December so far has featured a combo of chilly, cloudy, wet and raw and and a covering of snow.

GFS sniffing the potential down the road .......or maybe just tripp'in I am looking forward t the Euro and EPS run soon. I really feel the block is not figured out yet properly by any model, not to mention the vacillation of the PV near days 7 to 12.

This is right on the mark. I love seeing the -NAO action and it would appear the background state is more conducive to wanting to deliver cooler outcomes. No wild high amp warm MJO phases that stall, seems more so to a degree normal, versus last year at this time . If we get the Pac to improve things look very interesting indeed. I myself enjoy seeing the crazy vacillations in the in the vortex. The end of the winter might really feature some good Pac periods, contrary to some thoughts out there. Hopefully, blocking continues to show up. The vortex is suppose to get stronger soon, but I believe it is natural at this time of the year to be near interim highs. I would not be a bit surprised to see weakening by mid Jan to benefit Feb at some point ,and March especially. Just speculating but the descending QBO should kick in and be a more significant player by Feb. but as you know we are already getting some blocking episodes. This was a cool piece of info ( see below ) that I came across on HM's feed IO . The uncertain part may not be the weakening of the IOD, but more so how long will the lag effect take to wear off. That is the tricky part. Seems the standing wave had interfered with achieving the best outcomes from the MJO and tropical forcing. HM thinks that changes moving forward along with a few other mets. Things are looking to pick up around here soon. I have a feeling sometime before March 15 th there will be a KU event for the DC to Baltimore area. It fits the extreme nature of recent weather events and I feel the HL are targeting the Eastern half of the country this winter season. Anthony Masiello 2h The N PAC low/+EPO and Scand. look you see seeing in the extended range is actually a classic IO lag. But the next West Pac influence is already underway then.

Nice to see this .... it appears region 1.2 is cooling ahead of schedule. Of course we all know this region has a lot of volatility. However, we don't really want to have significant warm anomalies there. You can also see the slight changes starting in the IOD. Meanwhile the visualization at an attempt to weaken the IOD / standing wave further. Hopefully it works out, as it would match the seasonal progression.

A few members today on the CPC AO ensembles take it down to - 4 SD. LOL This is after what appears to be a consensus drop to - 2 SD early next week. The spread becomes very diffuse towards month end.

That is an interesting comment psu. I think we even see this in the EPS at times. Meanwhile Anthony thinks cold is coming, I am speculating it could be impressive eventually. ( and hopefully stormy ) This might have to do with the weakening + IOD, as he and Webb both recently mentioned, an evolving MJO and the evolution of sub seasonal factors. I also see a potentially more Modoki - ish type configuration as well in the Pac.

@psuhoffman Interesting , and there are consequences

I wish once this winter we get all the players to combine. I am not getting any younger. I found my snow shoes in the basement under the ping pong table this weekend , maybe that is a divine sign of things to come.

Yes, he gets these " not in consensus calls" right a decent amount of the time . I recall many of these the last 10 years. I wish he would put up when our KU window is. LOL Also his mid December shoveling reference made about a month ago ( although not a forecast ) fits as well , with this past week's snows in areas to our East and NE. , and also what might be coming up next week too. Not bad.

The December -NAO has become a Unicorn this decade. There seems to be some support moving later in the winter for a decent -NAO period, but so hard to predict even at short leads, seasonal NAO calls even more challenging.

Not sure the outcomes are really set in stone for the 12/21 threat period. Blocking will continue to evolve further and possibly even more significantly. I realize the Euro has better verification scores but with a period of high model volatility I would be open to any outcome. There is also some downward coupling from the weakened pv, coming up in the next 10 days. Afterwards, it is appearing the vortex gains strength per Amy.

I will be interested in seeing what transpires with storm tracks after 12/20, and more so after any moderation period. Seems we have been locked into several storm tracks per Bluewave. We all agree in December we really need an anomalous cold air mass and a very significant -NAO. No wonder why everyone is so gun shy regarding a -NAO in winter, and that goes double for December. Every year since 2010 has featured a + NAO in December. I am hoping to a get a fundamentally different storm track in the weeks ahead, one that benefits the Northern Mid Atlantic. Bluewave made an interesting post earlier today which I include below ( His thoughts work for our area as well ) ie. we need a favored MJO state and help from the NAO domain. : <<< "We are going to need a strong and sustained -NAO drop at some point this winter to get a more active benchmark rapidly deepening storm track. These transient wave breaks can only do so much with the very active Pacific split flow pattern. We tend to do better with MJO related -NAO drops and start warming events. " "The dominant storm track continues to be cutter and hugger. All our major storms this month tracked through the Great Lakes or right across the area. The next 2 storms look to take the same type of track. It will be interesting to see if we can get the benchmark rapidly deepening storm track more active in JFM." Dec 1-10 Next 2 storms >>>>>>

Interesting, thought it was colder out West. ( courtesy bluewave ) from bluewave: <<< The one given has been the big long range model cold bias across the CONUS in December so far. The cold was limited to the Northeast instead of spread out across the CONUS. It looks like the mild Pacific split flow had a bigger influence than expected. >>

Met John Homenuk stated he feels the issues to a colder and more snowier solution is better timing, less Southwesterly flow initially, and the elongation of the TPV in Central Canada needs to lessen.

First I thought suppression, and then saw the temps, yuck ! But, it might work out like Bob said. Wish the entire time period was much colder honestly. Don't mean to be picky, and yes, it is still out there a bit, changes will happen.

Glad to see you and psu are on top of this . Damn that is sweet !!!

Hearing the UkMET went South as well.

What does the NAO domain look like? Are we getting that Davis Straits blocking trend there after hour 96 ?

In my forum we say that the lack of all snow solutions are mostly climo related as we are not yet into our peak for all snow events. However, I get from your post that we could actually get better BM storms but are lacking the more desired West based NAO block. This too is very interesting..... getting enough wave breaking to help but not enough to achieve a coastal BM solution. I thought we were going to get a West Based NAO even without a MJO phase 8 1 ?

That makes sense. I think in the post above Space Weather thinks the min will be achieved in mid 2020. Some say we are already there. The receptive base state reference I thought had to due with the current atmosphere. The period you mention of max benefit being just beyond might be connected to a paper or two that states there is a lag effect possible - ocean current related/ SST etc. After a solar minimum it is thought the NAO domain might be more receptive to a negative state. I know Isotherm covers this. If this is correct next winter's NAO might be more so negative. One paper even stated there might be a several year lag after the solar min regarding certain pattern drivers, one being the NAO again.

Granted this is way out there, but on this morning's GEFS at hour 264 to hour 270 looks very interesting at 500. This time period has my interest. After this period ( Dec 20 th to Dec 23 rd ) I almost wonder if we take a step back and moderate , or if we continue on the colder side. The several days leading up to Christmas look like they have potential. I have not been able to say that for about eight years.

More on the speculation side, but I wonder the role the current very low solar min and lack of sunspots are having on the pattern. From what I read in a very low solar period, the solar background slightly amplifies whatever the base state is. So, if there was a base state that favored increased colder risk and less warmth, you would verify slightly colder versus warmer. It sure seems that is way this month has gone so far. Space Weather states we have not reached the lowest point yet, however, I know some experts use different data to decipher when they think the solar min has been achieved.

I like the mention here of 60 West . This is a cool animation.