psuhoffman

Gfs went the wrong way. Same problem as always. Too much going on in the NS. 2 doesn’t allow 1 to amplify. Im also kinda over getting excited when we see a “trend” in guidance that takes us from “out of it” to “slightly less out of it”. It’s a fallacy to assume that trend continues. This isn’t dead but it’s low probability. Don’t think I’m saying it’s totally not gonna happen. But I’m not getting excited until guidance actually supports something. I’m tired of entering the 100 hour threshold saying “we’re close if we just get this and that trend”. No. Screw that. That almost never works. We just get frustrated. I’d rather enter the final 100 hours with the preponderance of guidance showing a flush hit and not needing a bunch of things to change in our favor.

Yea of course the pattern matters. My argument was irrespective of the pattern the time since our last snow is irrelevant

2 problems with this narrative. 1) big (let’s say a widespread 10”+) storms dont just happen because of time. They happen when the pattern supports. Yes there is a random typical mean frequency to them simply because by random chance the patterns that support them tend to happen maybe a dozen times a decade and odds say we hit on several of those chances and so normally we will get several of them every decade. But if the pattern isn’t right they won’t happen just because it’s time. 2) because of typical frequencies within the variance there will be random patterns but it’s like a coin toss. The odds of getting 10 heads in a row is extremely rare. But once you had 9 heads it doesn’t change the fact it’s still 50/50 what the outcome of the 10th flip will be. Once you get 9 heads your chance of 10 is now 50/50 regardless of how bad the chances were at the start. I’ve done that math before to show that the chances of getting a big snow or a big year are about the same (if you ignore the pattern) going into every year regardless of what the outcome the previous year was. The patterns are simply random due to typical frequencies within the chaos.

It could. But how often in the last 5 years have we said that. And how often did some adjustment happen in the last 48 hours that actually helped in a significant way? The fringe areas will adjust of course. But it seems increasingly rare that we actually see major synoptic changes that move the core of a storm that much in the final 48 hours anymore. I think if we are really in the game we will see major improvements in the next 24 hours.

Some actually say and mean that…but for the most part 90% of storms end up hitting the general place they bullseye once inside 100 hours. There are some adjustments on the fringes but once we get to 100 hours the guidance has been really good the last few years. Seems between 150 to 100 hours is when the convergence on a close to reality solution happens. We’re in that zone now. And it’s trending better. Problem is that trend could end anytime and very soon I suspect we see guidance find something close to the final outcome and we still have a bit of work to do. We haven’t had much luck getting the SS to time up with the NS lately. Our best chances came when the NS simply dug enough to get it done itself.

True but it was the dud of the modoki Nino cohort

I don’t even want to get into this because there are people who live to argue definitions and classifications and I hate that. There are disagreements about exactly what a modoki is. Some classify them as any Nino that originated from the central pac then sometimes propagates east. Others by any event where the warmer waters are centered in the central pac. For our purposes even a basin wide is ok so long as it’s moderate not a super Nino. But we definitely want the warmest anomalies to be in the central pac. There doesn’t seem to be much pattern of regularity. I think there were modoki or modoki like episodes in 1964, 1966, 1970, 1978, 1980, 1987, 1995, 2003, 2005, 2010 and 2015. 3 weren’t great. 1980 was a nightmare where every big storm (there were 3) hit the southern mid Atlantic and north of DC was just cold and dry. 2005 was weak and didn’t couple well and we got kinda unlucky on several storms. But it was a good winter just not great. 1995 sticks out as the WTF went wrong in that group. 1980 and 2005 at least bore characteristics of a modoki Nino and we just got unlucky. 95 was just an anomaly like 1996 was in the other way.

https://www.nature.com/articles/s41598-021-97111-y ETA: for anyone that doesn’t like to read the short of it is that using this method apparently modoki ninos can be predicted in advance and they are predicting one next year.

It’s a decent setup on the southern part…but damnit with the NS SWs flying across every 36 hours it’s hard to time anything up.

No he has no idea The pattern is what it is. Absent blocking we need luck. We’ve had 2 major amplifications. One cut west the other was east. We had 3 boundary waves. One went north, one south, and we got one region wide 3-6” storm from one. (I’m not counting Jan 3, that was really during a transition from the -NAO -pna pattern). So in the first 4 weeks of this pattern we had 5 legit threats and 1 decent hit and 2 minor fringe events. A little frustrating but not a total disaster. Do we get more luck before this ends…I have no clue. But just like the others we wont know the details of any threats until they’re within 5-6 days. Stuff at 140+ hours will come and go and change a lot. Some keep saying stuff will pop up within 72 hours but I don’t really agree. I think guidance is better than in 2014. These waves have been modeled very well once inside 100-120 hours. But outside 120-140 things have gone through major synoptic shifts. I suspect we don’t go 2 weeks (the pattern looks to last at least that long) without some threat materializing but nothing is within range yet. But we will be at the mercy of the same factors. If it’s a boundary wave we need a weaker wave. If it’s a major amplification/phase we need perfect timing.

That index isn’t always the best way to judge. It’s based on surface pressures between Iceland and the Azores. That’s not really even what we look for. A Greenland block or even Baffin block is better yet sometimes won’t show on that index if there is a trough in the eastern NAO domain. We had a beautiful retrograding block from Dec 18-30. But the pac was historically bad. There was a ton of blocking last winter also.

The skepticism isn’t wrong. It doesn’t snow much here without blocking. But it’s annoying when the woe is me crowd takes over and the thread gets flooded with whining over what’s normal (not snow). It’s been a pretty typical winter. Some snow. Some cold. But not enough to make most happy. And that describes 80% of our winters. How many in the last 20 years truly satisfied the majority of people here? 2003, 2010, 2014, 2015…that’s it really. I was happy with 2006 but I remember people whining that it was really only one storm and it melted so fast. Same with 2016. So other than 4 of the last 20 years people some were complaining. Maybe they need to evaluate their expectations! Im not blind to the low odds of snow but my game in winter is to hunt for the next possible threat, whether it’s 3 days or 15 days away. And whether it’s in December or March. I’m hunting for that chance of a snowstorm and analyzing the pattern to identify our chances knowing full well it’s a long shot and most threats are bound to fail.

The southern and eastern mid Atlantic cashed in on a few waves and in places where avg snowfall is only 15-20” that’s all it takes. Anywhere north west of there all the way to Canada is having an incredibly dry snowless winter. Even the ski resorts in new england. It’s been cold so the conditions are ok but sugarbush averages 275” and is only on 85 right now. Some are doing even worse. I’m starting to get really worried about spring skiing. My favorite time is March and April but unless they get about 100”+ in the next might there won’t be any spring skiing. The pathetic base they have now wouldn’t last the first 3 day 50+ thaw or one good rainstorm.

If we can stall 4/5 a bit...the later we get in winter/spring the more they become ambiguous and not necessarily warm phases anymore.

Maybe after saying the pattern was going to break down for the last month they are finally going to be right. I am not saying they wont be. I don't know. The pattern does have to break eventually. BUT...why do the same people that say it means nothing and deb when the super long range guidance says cold is coming...suddenly believe it totally when those same models say warm is coming???

I’ll be at snowshoe with my kids next weekend.

Tuuuuuuuuucked

My perfect storm. Gives us 10-20” then obliterates the ski resort I’m going to right after it with 40”. ETA: my 10 hour drive to sugarloaf would have 20”+ otg the whole way lol.

If you're talking exclusively about 20"+ HECS storms, then yes the window for those closes around Feb 15th on the coastal plain. But those are extremely rare, like 1-2 per decade rare anyways. The odds we were going to get one of those in a nina was VERY VERY low anyways. But if we are just talking about a snowstorm, even a really significant 10" storm, the odds go down after Feb 15 but its not a cliff its a slow gradual decline until you get to late march where the door finally closes. The metro areas have had plenty of significant snowfalls in late Feb and March. Just off the top of my head there was a 8-12" late Feb storm in 1966. A 10-15" storm in late Feb 1987. I can't remember exactly what years but I know there were big storms (like 10"+) in both the late 1920s and late 1940's in late Feb. March 93, there was a pretty big storm in DC in March 99, A 6-12" storm in March 2009, a very big storm, I think 10-15" across the area in March 1960. I know there was a 8-10" march storm in 1976 and a big storm in March 62. I think there was a big march snowstorm in the 1940's also. Those are just BIG MECS 10" plus storms...there were countless 5-8" type snowstorms in late Feb and early March. The list isnt that much shorter than a similar list for early Feb or some random period in January even. Yes it lacks 20" plus HECS storms...but you made it sound like snow suddenly becomes harder after Feb 15th.

Correlation without causation is just a random fluke.

The weird atypical presentation is because of the combo of the STJ wave out ahead of it and the stronger initial low along the front to the north. The stj wave is the focus of the deep tropical moisture and the low to the north prevents any closed circulation. The combo means no typical WAA precip to the northeast of the developing low until it eventually phases.

I’ve seen that synoptic progression happen a few times. Not impossible. But it’s not something models will get right from range. And to work we need the secondary to pop southeast of us now right over us like the 12z Gfs.

I honestly rarely look but I do know at one point earlier in January they showed a total torch for February.

Very similar problem to last weekend. Not much was said on this but Imo what went wrong most was simply the timing of where the stj waves were. The ridge trough alignment was great. The NS SW dug far enough southwest. The problem was at the critical time as that SW rounded the base and looked to amplify there were two STJ waves, one in the western gulf behind it and one way off east of Florida. It linked up and phased with that one. That pulled all the energy too Far East. We would have been fine if a stj wave was in the eastern gulf coast at that time. Or absent that we would have been better off if there was no stj wave at all. The track of that NS wave was perfect for another 3-6” snowstorm like the one we had earlier this month if it simply amplified on its own along the arctic boundary instead of phasing into the stj wave.

What did the gefs and eps extended show for right now 3-4 weeks ago? I guess eventually they will be correct if they keep saying the same thing. What I’ve noticed is those long range guidance systems skew heavily towards “typical climo” in a given major base state. That’s why in 2019 they kept teasing us with the “typical Nino” look that never came. This year they keep wanting to revert to “typical Nina “ but something is obviously countermanding that. Im not saying they are useless. Going with typical climo for a dominant driver base state isn’t a bad idea sometimes. So when it gets “what’s driving the bus” right they can be useful. But when a season is not going according to typical for a given base state they tend to be awful and keep teasing a shift back to said typical base state climo.