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Better late than never. This is interesting as well image of above for Sept 2019

Snow cover continues to expand, looking really good so far .

From a met at 33andrain Posted 15 hours ago To piggy-back off of the above posts...The analogs that end up blockiest over the course of the winter have an Aleutian low and Niño-like tropical forcing in the fall. With the recurving Tyhpoon (coincident with a strong East Asian Mountain Torque) shocking the extra-tropics into a higher AAM/more El Niño-like regime, snow cover advance over Asia supporting continued descending Siberian highs/mountain torques through the fall, and strong sub-surface warming in the central Pacific recently, it looks good at this point for a blocky winter IMO.

This is a great thread to read. Really does seem things are coming together for a Modoki Nino .

This will be interesting to track in the months ahead. I know several mets who are very interested in the QBO and the impact it may have on the upcoming winter.

Heard this has to do with the recurving typhoon and this time the West chills and snows and the reaction in the East is building warmth. I read , as you know , you don't always get a trough in the East just because there is a recurving West Pac typhoon.

Going along with Webb's post above, and this post by Ben, the general look over Western Canada and the NW US should really put down some snow cover. Meanwhile things up North should really start to chill in the weeks ahead, as a reservoir of cold air develops due to the consolidating PV.

Looking at the West Pac and how the typhoon plays out, I like this post by Webb . If correct, this set up plays into a warm ending for October overall along the East Coast and then the potential for a flip further down the line in November if you roll things forward. Many seem to think recurving typhoons are a lock for a trough in the East but the latitude and general extratropical transition are key pieces to consider.

This is preseason training for the Euro as far as I am concerned. If it handles this set up correctly I will feel more confident about the Euro's forecasts regarding cyclogenesis in the winter months ahead. Go Euro !

Such as saying climo temps and snowfall for the winter ahead, thinking of going climo and then adding some additional warmth is a safe bet. Extreme snowfall forecasts are so hard to come by lately. However, so tempting to find the weather holy grail and being the only met to forecast out of consensus cold and snow. A fine line between hype and reality.

Ventrice ECM prediction ......seems warm always wins out, however, a significant averaged -SOI in Sept yields a very warm October . So there you go.

That makes sense, I believe I mentioned in previous posts that the summer -NAO average means little for the upcoming winter. However, to say the next winter will have a positive averaged NAO just because the last 8 winters did is not a sound enough reason for me. Thanks for your post.

@bluewave does this feature, the Newfoundland block and its circulation at the surface, contribute to any significant SST adjustments up there off NE Canada? Does it reinforce any cold pool and /or possibly aide in the typical - NAO sea surface pattern that some believe support a semi-seasonal -NAO ?

Rather impressive to say the least

In regards to this post by Ben I don't see the logic. I see persistence of the last 8 winter with an averaged + NAO , but to use that as reasoning/support that this winter will have a another +NAO , eh, not so sure. I like Dave's response as a counter . From Dave

A little more on the IOD. I agree it is an important driver but some years with a very positive IOD do not seem to fit this year. Figuring out the role of the +IOD as a driver this winter will be critical. I know HM is following this. May help with favorable MJO phases and possibly with the placement of tropical forcing as well. However, not 100 % sure about those possible relationships.

@WxUSAF the trend is your friend I like this, and as Dave mentions for two reasons, one we need the rain and for winter to produce we really need to get some coastal action going into the fall .

https://www.climate.gov/news-features/blogs/enso/your-eight-minute-speed-date-pacific-meridional-mode Pacific Meridional Mode

The post dealing with PMM he mentions the closet matches are : 67-68 59-60 16-17 92-93

@showmethesnow in regards to the above and the PMM this post mentions how the PMM provides different outcomes once we head deeper into the Fall season and the wavelengths lengthen. This progression, should it hold, will yield a very cold December. December

@showmethesnow might make sense to focus on PMM as well Excellent read to learn more https://www.climate.gov/news-features/blogs/enso/your-eight-minute-speed-date-pacific-meridional-mode To me this is a sensible post brought over form 33andrain from member Oglem Posted 11 hours ago Hey everybody, I just wanted to say thank you for sharing information on analogs, it really helped me out. I took a look for years with similar PMM and ENSO. I found 6 years with Jun-Jul-Aug PMM > 4, and they were 1958, 1967, 1986, 1992, 1994, and 2016. 1986 and 1994 were moderate nino winters, so I removed them since this winter is likely going to be a neutral/borderline weak nino winter, although 1994 wasn't too far into moderate territory. Here's the result: Looks like the core of the cold will be in the Upper Midwest, with some cold in the NE and a SE ridge flexing a little bit too. This is only looking at PMM/ENSO, though. Assuming the PMM stays positive, it has the strongest correlation coefficient for the Northeast and Southwest, so it does seem like it would contribute to cold in the NE. Additionally, the PMM is related to Central Pacific warming, so it should be a factor in our favor going into the winter .

Your thoughts echo some others , I believe Benchmark's possibly. He even thinks a marginal weak Nino is possible. I did read Raindance who posts on the Nino extensively mentioning Nino 4 corresponds to a warm December in the East, I was not aware of this. But, again, are other players going to appear to maybe shake things up in December to make it colder. Time will tell. from raindance These are the closest Nino 4 years for September (29.1C-29.5C). They are all El Ninos - but keep in mind Nino 4 is warming much more rapidly than the other Nino zones. That's part of why you guys in the East have had such trouble getting a cold December since Nino 4 is correlated to December in the East for temps. 1989-2018 Septembers in Nino 4 are 28.75C on average, compared to 28.11C in 1950-1979. If the 2017 Nino 4 reading was applied to the older average, it'd be +0.6C, but a La Nina still developed, one that had the coldest Nino 1.2 readings for a while: 30 to 40 years in several months. My interpretation is if we had data for 2005-2035 in Nino 4, you'd find it was only +0.2C, instead of +0.55C. There are plenty of years when Nino 4 is +0.2C against the "centered climate average", that do not become El Ninos.

The EPS concurs or should I say it did as of yesterday.

There are differences as you mention @showmethesnow in the Pac Take this for example below as posted by Ben

Nice post. Seems we are faced with various extreme drivers of the pattern the last several years and how they interact together, or which takes over if you will, gives us our sensible weather. Many unknowns at this time still. How will the extreme + IOD effect the winter, what about the tropical forcing and the progression of the QBO. So much to think about. Very fascinating. I liked the way Isotherm describes his method of looking at the future weather and it truly is a multi-step process with one step determining the next and then weighing things out and knowing what to choose and what not too.