psuhoffman

Maybe I missed a 384op map. I posted a 240 EPS anomaly map. This is the November long range thread not the purely “what’s the winter going to be” thread. The long range looks warm for now. That was it. Posting a day 10 ensemble in early Nov means nothing for what winter will end up like. It does mean the current long range looks hostile to snow. Oh well. It’s November. But I have had several warning level events by thanksgiving. I don’t expect one this year.

You’re looking too closely at one data point to see the pattern. There is a typical Nino pattern here, with an enhanced STJ and numerous storms sliding by to our south. Some years more of those impact us. Others less. This makes qpf variable since we straddle the NW periphery of the mean storm track. But that’s where you want to be for snow. Raw qpf is irrelevant to us getting a 20”+ winter (good for DC area) since that takes just 2” of QPF to fall as frozen. So whether we get 15” or 20” qpf in the winter season isn’t all that important to snowfall.

Had more than flurries...had a pretty good squall around 7:30, was too warm to amount to much, did briefly whiten the ground.

He liked a post from one of the crazies

May I refer you to a better source given your preferences

Everyone can’t even agree on what years are modoki. It’s much more a spectrum than many describe it. But you’re right the nature of the Nino matters a lot. I know 1992 was considered a modoki by some, enough that it’s listed as such in one paper I read and on a web archive. But the sst charts I use to get a better picture excluded data from 1991 and 1992 so I can’t see for myself. I know 1995 was also considered a modoki and it was a POS winter. I just try to guard against drilling down too much. In general a Nino gives a by far the greatest chances of a snowy winter wrt “normal”. But it’s not 90%+. It’s like 70% when all other enso is like 25-35% depending on the specifics. So yea we want Nino but it’s not “it’s definitely gonna snow a lot” just probably. And I’m hesitant to try to attribute what went wrong in the 30% of ninos that aren’t super snowy to any one factor because no one factor can be blamed for all of them. They said there is plenty of evidence that the eruption was a significant contributing factor. But how significant?

I don’t mean to say it didn’t have an impact. But we’ve had other ratter +AO ninos that had nothing to do with a volcanic eruption. Was Pinatubo the catalyst or just a contributing factor? Just speculating. There are so many anomalies in this game I always am skeptical of simple solutions. I am not discounting it, it was one of the two things on my list of that worry me most about winter. Unfortunately I think the research speculated that a -QBO makes it worse. Causes an inverse reaction to a typical -QBO Nino reaction.

There is some overlap here. There is correlation between the pacific loading pattern we want associated with a Nino and a -AO. Nothing is iron clad but its a fairly rare case to get a canonical nino pacific and a raging positive AO. So I think its fair to speculate "what happened there" wrt to 1992. But that doesn't mean we can conclusively say "Pinatubo" either. It's easy to do that as its an obvious anomaly that coincided with another anomaly but correlation does not always mean causation. It's very possible it was just a random fluke caused by a bunch of more discreet factors we can't fully fathom yet.

In 2009 October was solidly negative, then November went slightly positive before the AO tanked in DEC and remained close to record levels negative through the winter. 1991 the AO was negative in October also before going slightly positive in November...but then continued to become more positive through the winter season. Predicting the AO is the million dollar question and if you could figure out a reliable way to do that your services would be in very high demand! There are some methods out there, like Chucks SST method, that show better than random chance results, but nothing is all that impressive with reliably predicting the high latitudes at any leads beyond day 10 IMO. A couple of observations I've made over the years though... a very strong regime either positive or negative tends to have some persistence. But it can still be difficult to predict exactly when it will break down and often happens with little warning. But it's a really bad sign if you see a very strong positive AO developing around the holiday time period. It's especially bad if its supported by a central pacific ridge as that combo is the most persistent and can eat up a whole season. The writing was on the wall for a dead ratter season by New Years in both 2019 and 2022. Likewise a strongly negative AO equally supported by pacific forcing tends to persist as well.

That wasn’t my point. Even if you subtract those 3 NYC was still way above avg during that period. We were slightly below avg even with those seasons! About 2 years ago I made a graph showing that the correlation between NYC and our area used to be stronger. A lot of snow in one usually meant a lot of snow at the other. Relatively to avg anyways. But after 2000 that correlation broke down and from 2000-2015 north of 40 got dumped and we didn’t even relative to avg at both locations. I don’t want to get into all the whys or theories. We’ve done that. It’s depressing. Just pointing out we missed out on the last snowy cycle induced by a favorable atl and pac pattern unlike the 60s and the 20s the last cycle mostly only helped places further north

Except the 2000s and 2010s weren’t prolific here. They were only average overall and that’s with epic years like 2003, 2010, and 2014 skewing. Take those years out and it was a below avg period! A lot of those 40” winters in NYC were single digit awful seasons down here! Last year I even opined that one of my fears was that was supposed to be the good cycle but we missed out. If you look at the mean h5 pattern from 2000-2015 it should have been epic. But it wasn’t south of 40*. You can decide why that was. But for “some” reason we missed out on the last snowy cycle down here.

It’s really hard to see what impact it will have on the winter SPV in summer

Basin wide centered west of 120* can be pretty favorable at times...especially if they are moderate to low end strong intensity. On the list of things I am most concerned about ruining our winter the exact composition of the enso is pretty low, its way more good than bad imo. If this winter ends up a dud the top 2 suspects for me would be 1) the overall pacific base state and the warmer waters surrounding the enso region muting the impacts of the nino 2) The impacts of Hunga-Tonga and possible PV implications of increased Strat WV

That could hypothetically lead to a winter with a mix of southern sliders that cannot phase and get suppressed by the N stream, and late developing N stream dominant systems and clippers that affect areas further north...this would also cause a snow dead zone in between.... I wonder where that zone would end up???

What criteria did you use to identify analogs? I ask because there is almost nothing that all of these years have in common which is odd for an analog set. They are incredibly divergent and at glance seemingly random, with respect to every major global climate indicator we track. For example wrt enso its almost an even mix of Nina, Nino, and neutral seasons. Equally with PDO, QBO, Solar there is a mix of divergent seasons. What do these seasons have in common that makes them analogs to this year?

I just woke up

I agree with this. I don’t want people to misinterpret my bleak assessment of how cc is impacted our snowfall results during less than ideal patterns and cycles to mean I think we don’t get snowstorms or anomalously snowy seasons anymore. We can and we will. Even if the worst case is true and 2016 was a tipping point and the climate zones have shifted, say we do have a climate more like Richmond VA now….even then we would still get snowy seasons. Just less often. Brooklyn: I’ve often compared the last 7 years to the early to mid 1970s. Both featured generally hostile pac patterns. Both were our least snowy long term cycles. But the mean pattern in the 70s was actually WORSE! Look at the mean h5 from 1971-1976. The pac is very similar to 2017-2023 but the high latitudes was much more hostile also in the 70s. Yet the snowfall results were even worse in the current hostile pac cycle. Obviously without running a sophisticated model with initializations from both periods and adjusting for cc we can’t say for sure, but I suspect that’s where cc comes in. Without the warning since the 1970s the last 7 years would still have been a low snowfall period, but probably slightly better than that comparable period in the 70s which featured an equally hostile pac in conjunction with an even more hostile atl. None of that means we can’t get snow when the pac and Atlantic patterns both cooperate. My pessimism revolves around the fact that more of our seasons are flawed not good patterns. It always was that way. That’s not CC. But CC is making it harder to fight to a respectable snow total in those not great pattern seasons imo. This study seems to support my gut based on anecdotal evidence on that.

This was one of the best posts ever on here. Thank you! Truly epic. I was thinking this same thing with regards to how the statistical analysis could be conservative on the results because the whole storm track is likely also shifting north with increased ridging. Think back to all the times we popped a huge SER despite a stout NAO block. Such a shift could accelerate the negative impacts for snow, especially at our latitude!

33 and rain would still show up as a cold anomaly lol

You lose interest as soon as the back edge snows up on radar.

Yup and as incredibly rare as it is…some in here regularly complain about even some of those events on that list!! Lol

This happens after almost every big storm I can remember. Some might have a handful of cold days before the warm up…but invariably it warms, whether it’s the day after or 5 days, and everyone acts shocked how fast the snow melts. But fact is 20” will get obliterated FAST as soon as dews gets above 40 and that happens here regularly so it’s almost impossible for the DC area to get snowcover to last long no matter how big the storm.