psuhoffman

This might not be the most effective way to combat clickbait.

Euro op is similar evolution to Jan 2000

Chuck pointed it out yesterday, I love seeing the cold anomalies centered in the TN valley. That’s our big snowstorm loading pattern look!

It’s a really good pattern with ridiculous upside which is rare in a cold enso. The similarities to 1996 with the current look on guidance shows this perhaps has more upside that we would typically look for in a cold enso year but it’s important to remember we do get these high potential setups and they don’t come together and produce sometimes. Even if the pattern on guidance is legit we could strike out. But I’m encouraged. I don’t throw around 1996 lightly. Usually I dismiss the possibility of that kind of repeat pointing out just how much of an outlier it is. But I can’t ignore what’s staring us in the face and the potential that exists.

That was my threshold that would make a better outcome “possible”. If you look at all the anomalous snowy cold enso years some are slightly negative, but none are in that -2 or -3 range we were hanging out in. At the time I said it I didn’t think there was much chance we would get anywhere near neutral by January but here we are.

At least it looks christmassy

lol Im still cautious. Long way to go before we’re measuring anything. But most of what I do is just math. Playing probabilities. And the probabilities say -pdo cold enso years are likely to be garbage. But flukes happen. 1996 happened. 2014 happened. They aren’t the most likely outcome and you’ll lose betting on that outcome most often but they do happen. More likely than those level flukes one off storm flukes happen like Jan 2000 and Feb 2006. What I’m seeing opens the door to the possibility this is an anomaly year. That’s all. I’ll take my chances considering how things could look right now. Several years recently I was working on my “winters over” draft about now!

Look I know, but the fact is the best cold enso match to todays eps is 1996 and it’s not close

I will be tracking our incoming HECS on my fight home January 4th.

Merry Christmas.

Im less sure of the larger PDO cycle, but we don’t need a wholesale PDO flip we just need the current near record negative one to end. There are cycles within cycles of the PDO. Within the decades long larger cycles there are shorter spikes. We don’t need a crazy positive PDO. 2010 was neutral. 2014 was slightly negative. A lot of the snowy winters in the 60s were neutral or slightly negative. But we need the -2 to -3 dip within the longer -pdo to end. There is some regularity to these cycles too. The last 3 severe -pdo periods lasted 4-9 years. We’re now 5 years in so it could start to flip anytime now. But it might take a few more years.

I agree to an extent but I do think there is an applicable lesson to be taken from what happened regarding the long range teases in both 2019 and 2024. In both cases the dominant long wave influence was a strongly -pdo pacific base state. In both cases the extended guidance wanted to quickly morph the pattern into a canonical look for the SSTs. Additionally NWP did a similar thing day 15+ in 2021 when a kind of hybrid pattern dominated yet at range the extended often wanted to resume a more canonical Nina look. I think guidance is over weighting enso SSTs at range. I don’t know the physics behind it but that seems too much a coincidence. But that isn’t necessarily what’s going on here. Actually guidance is bucking a standard weak cold enso look. Now that doesn’t mean it’s right. Maybe it’s wrong for a different reason now but I don’t think it’s doing the same thing as last year fwiw.

Sorry it had to do that, I’m not back yet.

I share the skepticism but ironically the pacific was in a more Nina base state last year than this one so far. I don’t know what it means. I think enso is decreasing in impact, especially when it’s weak or in contradiction with the pacific background state. But let me be clear, when I say I’m interested in that look, it’s with the notion maybe we get a window where we could get a snowstorm. A. Singular. One. I’m not suggesting 2010 or 1996 are walking through that door. I’m just hoping for a 2006 or 2000 here.

In both 2019 and 2024 the epic blocking looks would start to degrade before getting inside day 10. Usually they were handing out around day 15-20 and occasionally would get inside day 15 but never inside day 10. If this look can survive a few more days without getting can kicked my interest will increase exponentially

100! What has my interest is that we might get a window where there is enough ridging up top that combined with the EPO actually increases our chances of a snowstorm. Enough that maybe we have a slight chance to buck the odds and get that one hit that can make a season. That's realistically all I am rooting for...yea we might eek our way to a few minor events, whatever...but honestly what will make or break this season is if we can get lucky, find a small window, and hit big one time.

Also 2019, its happened a few times lately, it also happened in Dec more recently. The combo of our source regions being torched and mid latitude warmth caused the SER to link up with the NAO block multiple times recently. But we still need that longwave configuration we just need it to not be too warm when it happens, and no I don't know how we magically make that happen...but a pattern that puts us on the backside of a trough with no blocking to hold the cold in when an amplification happens is not a winning formula either.

BTW, given my modest snowfall forecast for this winter...I did not expect nor predict we do get a big snowstorm...or even a moderate one...to get to those numbers we just need a few minor events. But that does not mean there is no chance and that I am not rooting for it. Just because I expect it to be a horrible year doesn't mean I don't want it to turn out better or that I am not looking for the chance it does. Flukes happen. 2000 was a god awful horrible pattern 90% of that winter...it very well could have ended the same as 2002 or 2008 or 2012 as a complete dud...but we got one week with a decent pattern and hit the lottery. I am rooting for that again. That can happen in any year, nina or not.

It's not a block, but it is a high latitude ridge. Yes there is a difference and a true block which always evolves from retrogression or wave breaking is better and that pattern is the best for HECS hunting. But not all -AO/NAO periods come from retrogression sometimes they can evolve from progression of a heat ridge into Canada and those correlate to snow here also! No not as much as the perfect unicorn retrograding block. But a regular good old high latitude heat ridge is still a legitimate way historically for us to get a snowstorm. This evolution is actually almost identical to what lead to the Feb storm in 2006. The pattern started with a full latitude head ridge in the east which got undercut from the west through pattern progression and lead to this... It's a baby steps thing...what we are looking at around New Years would have to be step one of a process that could lead to a favorable snowstorm pattern here a week later IF things go the right way. As for the hyper focus on the EPO... yea it would be helpful if the EPO delivers cold, but there is a reason the EPO along has absolutely no positive correlation to snowfall here! NONE, ZERO ZIP. Actually when I looked at every warning snowfall at BWI since 1950 the EPO of all the major indices I evaluated was the least important. I think more snowstorms happened with a +EPO than negative. The fact is we don't just need cold air, we also need a longwave pattern that favors wave amplification at our longitude! An EPO ridge absent other factors does not do it. An EPO with a positive AO/NAO actually places us in a northwest flow and waves are washing out on approach. It's really hard to get a snowstorm in that look. Worse, without any AO/NAO help when we do get a jet transition and an amplified wave comes along its not going to meet any resistance and so the return flow ahead of it warms our thermals before it arrives...we are too close to the backside of the trough and the warmth is lurking too close to our west for that to work absent other factors like blocking. Cold dry, warm wet. That's a typical EPO driven pattern! No not every single one, once in a while you get super lucky with a year like 2014 or 2015 or some fluke hits like in 2022, but that is the less likely outcome....its much more likely that pattern does not lead to a snowstorm. Just because most of our snow the last 8 years has come that way does not mean its now the best way to get snow...that is the reason the last 8 years has been by far not even close the least snowy 8 year period in our regions history! Yes if that kind of pattern persists over and over and over we will luck and fluke our way to some random snow once in a blue moon...but it will continue to be the way it has the last 8 years with below avg snowfall years and scraping by with long stretches of frustration. An epo driven pattern is not going to be our most likely path to breaking out of this and having a truly snowy period or getting a legit area wide snowstorm. And sure we take what we can get, if scraps is all we can get eat them....but we don't control any of this so why not root for more? It's ok to realize we probably aren't going to win the lottery, but its ok to root for it! Lastly, if we get a pacific to atlantic ridge bridge up top (and those are rarely blocks) and its just not cold enough...the pattern isn't the problem...its just become too warm is! This is a matter of degrees, sure you can do the whole move the goalposts thing and say well...if that is too warm now we also need the EPO ridge AND we need there to not be a torch period ahead of the longwave pattern, and we need cross polar flow and we need....OMFG at that point it sounds like we live in Atlanta now and the truth is its just not gonna snow much and its probably not worth even tracking. I mean even in Florida there is some checklist of anomalous factors that if they all lined up could lead to snow...but the point is their checklist is 25 things long and so its just rarely ever going to happen. If our checklist starts to go from 3 things to 8 or 10 or 15 at some point we've entered the "its just not gonna snow much" territory. But just because we have a thermal issue now does not mean the AO and NAO are suddenly less important, there is no evidence of that...it just means we are snowing way less. We still need those other factors to line up to have a good chance of a snowstorm...we just also now need MORE.

2021

@WxUSAF @Terpeast We’ve discussed evaluating how much snow we may have lost due to warming but I’d love to see if a reverse method was used to assess how much snow would have fallen around the area in 2020-21 had it been the 1960s. I say that because there were several times that winter analogs from the 60s were at the top. And it was a pretty good pattern with several perfect track rainstorms. I got 50” up here because my boundary was just cold enough with elevation. The boundary is waning the fastest. I’m curious to see if that was supposed to be one of the good winters in an otherwise bad period. Overall the pattern has been shite recently but we’ve always had a skewed snowfall distribution with big years surrounded by crap making up a large portion of our snow. If we were to lose just say 1/3 of those big years it would have a catastrophic effect on our snowfall. We had this mean H5 for the core of that winter and only higher elevations cashed in! Thoughts?

It’s been requested I keep negative posts not directly about the current pattern here so here goes… CBM: Yes the negative anomalies are centered over us and have been…but it’s not enough. I’ve wondered this when seeing some of the isolated cold pockets out west the last 10 years…”would that even do it for us if it was centered in the east”. As we warm these tiny cut off pockets of cool just aren’t gonna cut it. Yea we could get lucky if every synoptic variable is perfect but most of the time it’s chilly but the cold airmass doesn’t have the depth necessary to withstand the WAA and return flow ahead of a wave strong enough to give us a decent storm. The only time it’s cold enough in these shallow cold pockets is on a NW flow. So we get cold dry warm wet. frd: exactly but the issue is if you look at the loading pattern for all our big snows that feature a trough just off the west coast and a split flow which floods Canada with pacific maritime. Canada was warm during almost all our snowstorms and that’s why almost all our snow comes with temps not too far below freezing. There are rare exceptions but warm everything just a few degrees and DC loses the majority of its snow! The issue is these pacific maritime intrusions used to being +5 or +8 not +20! Recently the pacific intrusions have warmed out source regions so much that even when we get a perfect setup it’s too warm. We have to hope this changes when the pdo flips, and I’m hopeful that will help. But I’m not sold the pdo is 100% of the issue.

I remember people complaining because the snow melted fast because it got into the 50s 3 days after the storm. Imagine that now. How the mighty have fallen.

I’m sure he could throw that in for free, what with the holidays and all.