psuhoffman

If we want to hold out hope the current global sst anomalies aren’t far off from this time in 2013. @Maestrobjwa if you want to know why 1996 was so good, the first half of that winter was dominated by a good Atlantic and pacific. A pronounced Aleutian low and west based NAO blocking. The second half was much more variable but with recurring periods of Enough blocking to score a few more snow events. If your asking for a predictive reason...I can’t say for sure. Even now looking at the sst anomalies leading into that winter I wouldn’t have expected that. Sometimes anomalies happen and we don’t fully understand why.

When you start parting into such specific criteria you end up with not enough samples to get any meaningful results. Even 15 isn’t really enough of a sample to say much other than generalities. But there seems to be an even mix of decent Nina’s and dreg ones in both the +/- QBO category.

This focused on DC but it has some significance here also so I’ll copy it. There has been some discussion about QBO correlations and Nina. My findings don’t show much truth to that at least wrt snowfall.

@CAPE I’ll post the h5 composites later when I have time but looking at the last 15 Nina’s going back all the way to 1984 I see absolutely no significant correlation between the QBO and snowfall in our area. 1996 skews things horribly on those plots. Truth is 4 of the 5 worst Nina snowfall years in DC were negative QBO. 1989/2001/2008/2012. The one awful positive qbo winter was 2017. On the other hand if you take out 1996 the 2 next best snowfall Nina years at DC we’re 1986 and 2000 both +QBO. Truth is other than 1996 Nina’s all are a range between totally god awful and average wrt snowfall. With the stj absent in Nina’s getting above avg snow is just VERY unlikely. But the QBO does not seem to have any statistically significant predicting value on differentiating between the really awful Nina snowfall years and the decent ones. When I have time I will look at the enso profiles (East/West/basin wide Nina) and north pac SSTs to see if one of those is a better predictor if Nina outcomes. Hopefully not north pac sst as those look like hot garbage right now also.

14/15 and 15/16 went about what analogs would have suggested. 2019 wasn’t far off for a weak nino. They can go either way and usually end up near normal. It’s really moderate ninos that have tended to be the big years. That said all your criticisms of analog forecasts are true. Problem is with seasonal forecasts there isn’t much choice. You can’t really forecast pattern progression for months out in time. So we’re left looking at past progressions for clues. “Analogs”. Now I think SST analogs are becoming problematic given the changing base state of the pacific right now. Isotherm might be into something with using other factors to predict global patterns. But it’s still the same principle. That’s why seasonal is such low skill.

But there is always a positive. JB didn’t have last winter as the primary analog. Only the second. The first analog was 2017 and that year DC had 3.4”. Thats 500% more than last year!!!!! Boom.

Like I said above it’s way too early to say anything is a lock so maybe the winter turns out ok. But you are looking at this wrong. It doesn’t matter how often people who have a cold/snow bias bust when they predict cold/snow. What you need to look at is what is their track record when they go warm. Because in JBs case it’s pretty damn good. Now that’s not a compliment to him. It’s not a fair metric because he only forecasts a below avg snowfall winter in the mid Atlantic like 2 times a decade (ridiculous considering that’s about how often we get above avg snow) when it’s so obvious that it’s probably going to be a dud winter that he gives up the hype and uses those years as a chance to save some cred. But still when the pattern drivers are lined up so god awful that even the most epic snow hype weenies are saying it’s not going to snow that is not a good thing! Surprises happen. Maybe things flip by December. Or maybe we get lucky in an otherwise crap pattern a couple times and that’s all it really takes to salvage a decent winter by our standards. But let’s stop pretending seeing all the typically snowy forecasters saying a snowless torch winter is coming is a good thing. Sorry I’m not a “denial” kind of person.

We very well could have a snowy winter. Sometimes the weather just does what it wants. But just because a forecast busts when it went cold doesn’t mean we want to see everyone going warm either! Fact is a cold snowy forecast is way more likely to bust just because our climo is skewed that way. We typically get 2-3 really good winters a decade and the rest are petty meh. Those 2/3 good winters inflate our average and our expectation. But the majority (even before global warming) are warm and every flake is a battle. And when even reliably cold biased outlets are going warm there is a legit reason. But every once in a while we do get a pleasant surprise. I’m not saying there is no hope or give up. But pure odds say we are very likely headed towards one of the “meh” years. Even so that doesn’t mean it has to be as bad as last year. Many of those years at least feature one or two fluke snowstorms. So even if the year as a whole goes poorly we will still likely get at least some opportunities and tracking. Just keeping my expectations pretty low for now.

I’ve gone through the records back to the 1800s and other than in the 1960s that was never a common thing.

We’re good no beef don’t worry.

Thanks again for the compliment. He is entitled to his opinion. He does have a point that the way we discuss long range threats is most definitely not aligned with how you would issue a public forecast. But that’s not what I’m trying to do. Typically when I’m stuck in the long range thread because “now” is a crap pattern all I’m doing is trying to find hope for the suffering snow weenies and analyze our chances of anything. But if you take that as a “forecast” I could definitely see how you would get the impression I’m awful and over hyping snow. If every-time I say a pattern has “potential” was taken as a prediction of snow...well I would be up there with JB! All I can say is it’s not intended that way. But I can see how it may have come across that way to him.

Thanks. Don’t read too much into my off handed winter comments “yet” as a lot could change but I don’t see a whole lot to get very excited about wrt winter prospects.

Any “long range” forecast will be pretty awful most of the time! But again I think you are misinterpreting our long range discussion. When DC spends the vast majority of winter stuck in a no hope pattern it would be pretty easy and boring to keep saying “it’s probably not going to snow”. It would be accurate. But boring. We we tend to focus on looking for any hint and discussing ways the pattern “could” evolve to give us any opportunity. Sometimes that’s getting excited over a pattern that may elevate our chances from lottery level to say a 25% chance we luck into an event. The kind of odds places further north would probably ignore! But it’s all we got much of the time. When myself or bob or Showmethesnow discusses what we need to see happen or how we want the pattern to evolve that’s not a forecast. Kind of just a speculative “this is how it could possibly snow if we’re lucky” thing.

Its all crap. Sst in the mjo domain is opposite what we want . Pdo. Enso. Atlantic everything isn’t right. I’m not wasting time debating which awful is most awful.

My scientific analysis of that sst chart

@Bubbler86 interesting points. But I know when most of us in the Mid forum post about anything day 7+ it’s meant as an analytical discussion of pattern possibilities not a forecast. I don’t think issuing a forecast for specific weather past day 7, even day 6-7 is a stretch honestly, is a good idea. I know some people take that probability and pattern recognition analysis and run with it as a forecast but whatever. Furthermore, the reason we do that is usually because there isn’t much going on in the day 1-6 range. Especially lately. You can always tell we’re having our typical crap years when the majority of posts are analyzing day 14 ensemble trends and MJO plots. I would much rather be analyzing vorticity, moisture convergence, and VVs to try to predict meso scale banding features that picking apart day 10-15 ensemble progs. Unfortunately there haven’t been a while lot of legit threats to make it into range to do that recently so reading the super long range tea leaves is all we have. Last year I said I thought winter was going to be a total dud in late December and made a long analytical post explaining why. But I said I would continue to track just in case either I was wrong or we lucked into a fluke somewhere. But a post on some possible glimmer of “hope” at day 10-15 should not be confused as a prediction for a snowstorm!

About once every decade JB does go warm/snowless and it’s usually when it’s so obvious he might as well use those years to save some modicum of dignity.

I think you should go investigate

I’ve mostly avoided the school discussion because I am biased and I truly believe everyone is coming at this with good intent and no one wishes harm on anyone so I really hope no one takes this the wrong way. I don’t begrudge anyone’s opinion on here and I don’t take anything anyone has said personally. And this is not in any way a response to anyone here. This is coming as a response to stuff going on in my district and some of the discussions I’ve had lately about that. But you all are my online family and so I feel the need to share what I’m feeling right now. I hope no one takes offense. That disclaimer aside...I am truly angered and feel disrespected by the dialogue my district and my own union are both taking. The district has been very clear their only concern is student health. And worse my union have taken up a false flag “kids could die” campaign because they also don’t think my life is a big enough deal to make the argument over. Which is insulting since they represent ME!!! I have asthma and Crohns and I’m not as young as I used to be. And I have 2 children I love more than anything else and I think about every minute of every day. I am not going to lie and make this about anything other then what it is...I am concerned about my health. And I am frustrated that the school district and at times my own union make it seem like I should be ashamed of that. Like my own life isn’t worth enough for that alone to be a valid enough argument. I am not and shouldn’t have to apologize for looking out for my own health and thinking about my family.

I saw something similar when researching something else last year but the correlation was very low. However, what it definitely indicated was a summer/early fall -NAO has absolutely no predictive value to a winter -NAO. I brought that up when DT used the prevalence of last simmer/fall -NAO in his winter prediction. I’m not sure a summer -NAO necessarily has high predictive value of a positive winter NAO though. Some correlation though but low from what I remember. Makes sense. The mechanisms that could cause higher polar heights when the pole is at its warmest and the atmosphere is thicker would differ from what might impact and weaken the TPV when at its strongest! It’s a totally different situation.

Yea except you don’t know our climo. In a nino winter our area and NYC can often have similar climo. It’s not that unusual for places in our region to best NYC snowfall in a nino. But in a Nina it’s a different world. Almost all the “good” Nina’s you refer to from time to time 2001,2009,2011,2013 (yes that was cold neutral but it followed 2 Nina’s and behaved like a cold Nina archetype) 2018 were utter garbage crap snowfall years here! 1996 was the only truly “good” snowfall Nina winter in the last 50 years here and 2000 was about avg across much of the area but memorable for an epic storm and 10 day period. The rest were pretty much garbage snowfall. We’re too far southwest to cash in on the northern stream miller b’s that are the main snow threats in a Nina. It took ridiculous blocking in 1996 (and March 2018 for a more contemporary example) to get our area into the action in a Nina.

When it’s January 15 and we’re analyzing the 800h Gefs for a possible March save...

Do we ever this time of year? But we can be fairly confident there won’t be a nino. And the sad fact is in the last 25 non nino years only 2 were above avg snowfall in DC. So simply using that we only have an 8% chance of a “snowy” winter. And if you remove the 2 extreme outlier non nino years (95/96 & 2013/14) the avg snowfall in the other 23 years is only 8.6”. So purely from a climo probabilities standpoint the odds say to expect about that. And there is currently nothing that would scream to throw those probabilities out. All that said pure probabilities aren’t a sound forecast because outliers are a very real thing. Maybe we get another 2014. But the odds aren’t good and att there is nothing that would hint that’s coming.

I’m not sure he realized my shot across his bow the other day was simply his own post to me from last December copied word for word.

I think DC has a very good chance to get 200 to maybe as much as 300% of last years snowfall this year! I know I’m a weenie optimist...