weatherwiz

Absolutely. Something fun to track over the next week. Kind of hoping that HP can act in our favor and maybe help suppress a bit but like you said...too early for these type of details. Can iron that stuff out early next week.

Regardless of track and evolution, I think it's fair to say that period of going to elicit a pretty significant pattern change across the CONUS. Whether it is transient or something that holds for a bit we'll see as the signals are a bit conflicting but if that pattern can hold we certainly should have some winter threats. Probably favored more as the pattern breaks down a bit.

That is one deep trough on the GFS for Thanksgiving week...and it probably still isn't done amplifying given the jet streak is only beginning to round the base of it lol

Yikes...that is pretty frightening. Great post, can't disagree with this at all. Weather forecasting has become a very hot commodity with a rapidly growing private sector. As skills have improved with short-term forecasting the envelope has certainly expanded to dig deeper and further out. You're absolutely right though, there has to be a realistic approach and understanding about its value. From what I see with a lot of long-range/seasonal stuff out there (though this may not apply to vendors who provide this stuff for clients) the communication aspect needs to be significantly improved. Often times on social media you'll see the posts looking at the D10+ day progs and it comes across as if that should be the expectation. Now most in the field (whether its professionals or hobbyists) probably understand that is not the case - but the issue is this type of information gets to the general public who don't know how to understand or interpret this information and all hell breaks lose (cue the hype machines). Long range/seasonal forecasting is something I've always been very intrigued in and I'm gad I've finally been able to get time to dabble into it this past year. I've found that through research of historical patterns, ENSO, teleconnections that I even feel like it's positively impacted my short/medium range forecasting. There are also negatives with this. There are so many companies emerging who "promise" they have all these tools and can pinpoint things down to city level so many days and week out and wow people with pretty graphics and cute colors and essentially suck people in and just steal their money.

I think I remember that event (obviously from watching TWC). IIRC that was a very active winter across the Southeast in terms of severe weather/tornadoes with several big outbreaks. Maybe even one in the mid-Atlantic?

For sure. For those like correlating anything and everything to New England snowfall, is there any correlation between ANC getting smoked and us

I'm sure those in Anchorage may surely welcome that

Going down to Florida for a week Dec 23...I have to remember to be on the look out for some severe threats down there between the 23-30. Hopefully a moderate risk derecho event. I'm just hoping the big one doesn't happen up here that week but it probably will.

GFS gets that PV lobe much farther south while the Euro keeps it confined much farther north

yup...these meso-low signals often throw wrenches into the mix

Pretty much solely tied into phasing. Phasing situations drive me nuts because so many put too much stock into SLP and QPF charts. If there's a phase there will be impact and if there is no phase there will be minimal to even no impact.

Obviously long-range isn't my thing, but I've spent a great deal of time the last year really digging into it more and looking at composites for all EL Nino events but I as well think there is too much weight being thrown around on a warm Dec just because it "fits" the mold of EL Nino or stronger events. Not every single EL Nino event (regardless of strength) has produced this. I think people get too caught up in just looking at general composites. Certainly a general composite is going to give you a mean (although there is always a risk that mean can be skewed) but you have to run each individual (month, season, etc) against the mean and when differences arise, explore what caused those differences.

Certainly can't be a bad thing to see some PV displacement into our side of the hemisphere this early. I suspect this is something we'll see several times moving later into Dec and into Jan

Looking at this sends chills down my spine I feel like it's been a while since we've tracked such a look during the winter. There are sizable differences though with the evolution of that trough digging into and progressing across the Ohio Valley later this week so right now anything is on the table. The GFS seems a bit more consistent though and has trended in a direction of a phasing scenario.

You snooze you lose

Pretty decent warm core. +15C or so at 850

Probably even a pretty solid snow event for the ski areas in northern VT

If this were even 4-6 weeks later this would be some big time excitement in terms of tracking

hmmm the 12z GFS is going to be a tad interesting me thinks

I mean how often do we see significant winter storms before Christmas? How many of our winter's are generally "front loaded". And I don't count getting 15'' in December with a seasonal total of 32'' as "front loaded". December we're still eradicating milder temperatures and building cold into southeast Canada. Moving into March we're still more likely to have a significant cold source around.

Yeah I don't see why there are always so many freak outs for lack of snow in December or even November. I would figure pretty much everyone in this region's climatological max for snowfall is January/February. This has been mentioned a million times before (although not sure if the past 10-15 years has changed this) but at least BDL used to average more snow in March than December.

This is an area I want to really brush up more. I think a lot of our signals (looking in the 6-10 day...maybe even a bit further out) really start from this region. The last few winters we all kept getting excited for these "great" "positive" pattern changes being modeled 7-10 days out and they never happened. My hunch is 1. the changes were the result of changes within the SLP field and jet over this continent 2. Those changes never verified over the continent so we never saw the changes happen here. Essentially, what I'm getting at is if forecast models are signaling big changes 7-10 days out here and it steams from changes over Asia/Russia say 3 days out...it's important to look at verification of the fields over Russia/Asia/ If those changes didn't happen then chances our we're not seeing much change either. This is all just simple classification an of course.

That's probably a better method than just a raw index itself, thanks!

do you know where to get MT/AAM data these days?

As always, this was very thoroughly done and a great read. It makes me very happy and I feel a bit more confident that we are pretty much on the same page as to how this winter will evolve. I enjoyed your sections when you went into the Walker Cell/Hadley Cells into great depth and how you focused on the lack of gradient within the Pacific with retrospect to SST's and SLP. This is something that I noted as well but didn't go into great depths about, neither within my post or with analyzing. One big difference between what we've done with the breakdowns is you did EP, Basin Wide, and Modoki breakdowns. I did not have a basin wide category. Perhaps my favorite part of your outlook is the depth you go into regarding the background warming as a result of climate change and how that needs to be factored in. The RONI and EMI are something I'm going to further explore as well. I will be re-reading your sections on solar/volcanic impacts on the stratosphere several times. This is a subject I have little knowledge in and you really break this down to where it's easy enough to develop a building block to learn from and further explore.