psuhoffman

Honestly looking at the individual members this run is identical to 12z. The difference in the mean is at 12z there was one member with 30-40” directly over us. This run there are 2 crazy members like that but one misses just north and one just south and so the mean looks less impressive. But looking at the scope it’s a very similar spread and the probabilities of snow look about the same.

I don’t have time (nor do I think it’s worth it) to dig deep into it but from a quick eyeball of the individual members it doesn’t seem any are true cutters. There are 2 that amplify too soon for our purposes but still track west to east under us and bring some frozen precip to the northern parts of this forum at least, but the big snow is PA line north. Then there are a bunch of op euro looking solutions that miss just to the southeast with the best snow. The rest seem to be a camp that fails to get its act together between a northern and southern wave. The northern wave weakly slides over the top and the southern is suppressed. Some of those might be giving the impression of a cutter. But they aren’t big snows anywhere just a split system with a weak wave to our west. It has a lot of spread which is to be expected at this range.

for 60 years DC averaged 4 snowfalls a season of 1" or greater. For the past 20 years that has dropped to 2.9 and over the last 10 it has dropped to 2.4. Furthermore, its worse when you dig into that. It used to be rare to get a season with less than 3 snowfalls. For a long time 3-5 snowfalls per year was the common and anything above and below that was rare. Recently we still get the rare season with 6 or 7 snowfalls but what is happening is in the rest of the seasons suddenly getting only 1 or 2 has become common. What used to be rare, getting less than 3 snowfalls in a whole year, now is happening regularly. It was never easy to get snow. But it was easier. And I have noted recently that we seem to need increasingly anomalous events (crazy combinations of arctic air with uncommon storm tracks, ridiculous wave spacing, perfect timing) the kinds of things that just aren't ever going to be a repeatable staple to get reliable snow regularly. The most common way to get a snowfall in prior eras was simple...get a wave to slide under us and have enough cold air in place. Lately...unless we get a string of anomalous events the cold part is simply missing. My point was I would like to see us get snow in a way that is repeatable. Simple. Easy. Anything that takes a congruence of several unlikely events all going our way to get snow is unlikely to repeat very often and doesn't really give hope we have broken out of this funk we are in.

The joke is it doesn’t happen as often as I reference it and in the end over longer periods it doesn’t matter because for every fringe there are 5 storms that we get more. But…the fringe is real. I’m at the northern edge of this forum at 1100 feet. If we’re discussing a legit threat for the greater DC/Balt forum then by far the bigger risk to me getting left out is for a fringe. Odds of it shifting so north I get all rain are slim. Fringes happen here usually at least 1 a season but in a normal season they are offset by 4 storms we stay snow and south mixed. Last year was an anomaly.

On a more positive note...the GEFS went the other way, still has more phasing with the Jan 11 system which leads to an even stronger 50/50 feature 12z v previous runs...and a colder look for the threat on the 15th. So a better/colder outcome is very much still on the table. But my point is still valid... even if we do actually get the ridiculous course of events needed here to get snow...doesn't change the fact that I would like it if we didn't need crazy rare things to all happen perfectly in a convoluted domino setup for us to simply get a snowstorm. I would like to just see a freaking simple wave slide under us and have it be cold enough to snow without some crazy progression.

The track isnt the problem, the high isnt the problem. The point of a "perfect track and high" is to create the "flow" needed to get cold air or keep cold air over us during the storm. If there is simply no cold air it doesn't matter. What good is a NE flow if the air to our NE is warm also? The issue here is some past runs phased a super bomb to our NE which created a ridiculous northern fetch behind it and drilled what cold there was way up in Canada all the way down into our area in front of the storm. This run that feature wasnt there and so all we have to work with is what we usually 99% of the time will have to work with which is whatever air mass is immediately to our north...and its crap.

IMO the bigger issue here why we don't get a frozen event out of the GGEM/GFS 12z permutation is simply a lack of enough cold. YES if we want to drill down to specifics the failure of the Jan 11 system to phase into a sub 960 bomb cyclose and stall in exactly the perfect location is why it went from a cold enough to not cold enough solution this run. But take a step back for a second...if we are relying on a complicated multiple stream phase into a super bomb cyclone that stalls in exactly the perfect location to get cold enough to snow...well umm...come on man. Was that ever really something we were expecting to go down exactly like that? What happened this run is the phase didn't happen but we still ended up with enough confluence to our northeast, a 1040 high, and the correct wave spacing such that the system is forced under us. The storm tracks from St Louis to Georgia then the Outer Banks and up off the coast. The problem is there just isn't any cold air. It's raining to Canada with a low off the coast of NC! If there was even just anything close to a normal January airmass in front of this...with a 540 line like near DC v up in Quebec, this would be a frozen event at least to some degree in our area. Sure focus on the failure of a perfectly placed triple phased bomb cyclone to drive cold 1000 miles due south in front of the system if you want. But if the only way for us to get snow is through some ridiculous nonsense like that...well ya know my take. Yea I know, but I'm trying real hard not to go on and on about this and annoy everyone...but damnit crap like this isn't helping.

Some 30,000 foot thought this morning Good, the high latitude pattern (which I’m including the prevalence of a Hudson high here) is good enough we probably will continue to have hope for these random systems to cut across and if we get lucky time up with cold. It’s a long shot pattern but not completely hopeless like it would be if we had a raging positive AO like 2020. Bad, the PNA spike, if we can even call it that, is super temporary. It leads to one shot and then we go back to a very warm look. The hope that the pacific was going to quickly morph to a more favorable look is fading. I really hope we hit on one of these long shot threats the next 10 Days or it could get insufferable in here if it’s Jan 20th with no measurable snow and nothing but torch on the horizon.

He actually has proved something I speculated about before. By showing that when other factors are bad the mjo cold phases don’t really correlate to cold it confirms that the mjo cold phases really only have a lot of impact when the pattern base state is cold. When we’re in a modoki Nino with a -QBO and low solar then sure it correlates to cold lol.

OK please forgive me for the late night possibly impaired rant but I am putting aside my science hat and gonna release my inner Ji for a moment here.... I HATE THOSE GUYS...like hate hate hate Furtado with the fire of a thousand suns. He has always been right btw, but he only seems to pop up in my twitter feed or on here when its to tell us how the MJO or some other tele isn't going to actually cause cold like we expect because of some other intervening countermanding factor. He did this years ago showing how "actually in a nina and a -QBO Phase 1 is actually warm" crap and another time it was "during high solar and a strong PV Phase 8 is warm". Now its "when the PV is strong ALL THE COLD PHASES ARE WARM" WTF. And I have repeatedly asked him "then what correlates to cold during these conditions" and he has never once answered...I guess we know the truth NOTHING DOES. Again, he is always right...but its annoying that he always shows up to explain just how FOOKED we are lol. Oh and this is why I don't waste time on the MJO like some people. Look at the correlation charts...the warm phases have a super high correlation to our temps...and the cold phases have almost no significant correlation! So in other words when the MJO goes into warm phases we are definitely screwed...but when it goes into cold phases...it might not help us at all. Great. And if you really want to get depressed last year someone posted a chart that showed over the last 20 years just about NOTHING correlates to cold in the east... lol Sorry rant over, just had too.

They aren’t meant to be forecasts. They are simulations meant to be tools to make a forecast. The simulations incorporate so many variables and have to make so many assumptions where there are unknowns it’s totally logical that there are different permutations each run. Again, they aren’t a forecast, just a tool.

I agree with the skepticism, our base state has been suck, but this is overly simplistic. 1/96, 1/00, 2/06, 3/09, 1/11, 3/18 all were big storms in a Nina. We can get a snowstorm in a Nina. With the exception of 96 we just never string together multiple hits to produce a big season but one storm can and has happened quite often.

I’m ok with a suppressed solution at 200+ hours same as we used to be ok with that at 100 hours decades ago. It’s going to adjust in some ways. 50/50 chance those adjustments are towards less suppression.

I said I was "interested" and that is all that is worth saying until we get it inside about 150 hours or so. That is about the magic range where guidance has converged on the details that determine the outcome of these waves. But from this range everything is there I want to see. Its a good setup, pretty classic way we get a snowstorm really. Just have to wait. Keep in mind though, no matter how good the general setup is...even the absolute best threats are still way below a 50/50 bet at this range. This is a good look, but that just means we have a 25% chance v a 2% or 7% chance of snow during any normal period at this range. @CAPE you're 100% right about the transient nature of our 50/50's but a lot of snowstorms come from that. We actually want the 50/50 to slide out as the storm approaches. A lot of our best storms came after blocking actually broke down. There was no blocking by the time Jan 1996 and Jan 2016 happened...but the course of events was already set in motion. There was no blocking in Feb 2003 either just even more lucky timing with the 50/50. I am NOT comparing this setup to those, no one should expect a HECS here, although I do think this setup has decently high upside if it goes right BIG IF THERE, but just pointing out that a "transient" 50/50 isnt the worst thing in the world. Very few of our snowstorms actually come from absolutely perfect setups in every way just because that rarely happens. That's also why its frustrating when we keep failing with flawed but decently good setups. Yea people are right when they focus on the very specific minor flaws that caused the fail...but by the same token we should be hitting some of these. Our luck has been REALLY bad lately. The we're due index needs to kick in soon here.

Hey I get 6 minutes of snow before the rain up here!

You’re always such a ray of sunshine

That’s the bar now? Rooting for a repeat of 2002. Lol

Euro and GGEM are keying on a different SW than the "threat" the other day. I didn't like the angle of the other threat, amplifying too far east, I've seen how that ends multiple times the last few years. This one has more space to work with and is amplifying far enough west for me to think it has a shot. In the end temps are more likely to be the problem here not track.

Ok now I'm interested

This is the one setup that has my interest "some". It's not a high probability but its a workable enough look and high stakes enough (if it did go right and max potential it could be the kind of storm that makes a season itself ala Feb 2006). But my god the airmass...ugh. The airmass kinda reminds me of Jan/Feb 2021 a little. Maybe you all will have to come crash up here for that one.

There is a spectrum to this. But when we are talking about any airmass that isn't initiating from cross polar flow out of Siberia we are talking about some degree of pacific maritime influence. But there is a big difference between air that originated in the North Pacific then crossed the Yukon and air that was injected directly into the CONUS from the central/south Pacific. Maritime air that originated in the central or south pacific was never going to work in any era. But recently we have seen the failure of airmasses that originated off the north Pacific then mixed with continental air over NW Canada before tracking into the eastern US. This week might not be the best example of that. The airmass is pretty bad, it does have some air injected from Canada but also some air straight off the Pac. But the thicknesses are low and the warming is happening in the boundary layer most dramatically so that is an argument that this might have worked 30 years ago. But there were better examples recently where we had air that IMO had enough continental influence that it should have been workable and wasn't even that close. IMO it's not any one single event, its that we've had so many marginal setups over the last 5 years and they just about all failed. Should all of them worked out, no. But some should imo. But I want to stop beating this dead horse. I've said my peace. Everyone knows the deal. People can take whatever opinion they want on this, nothing said now is going to change it. The data is there, we've debated it, everyone has made their case. I don't want to continue to beat this drum. We can have another discussion about this once the season is over and people are less invested in snow in the moment.

When have I ever been that way when it actually snows???

I knew your post wasn't really critical, I tried to indicate that in the last part. I am more pessimistic this year though. That is irrespective of my concerns with climate change. Even if this winter was 30 years ago I said back starting in late summer and through fall that just about every indicator I could find that has some correlation IMO with winter was wrong. This was likely to be a bad winter in any era, but add in our recent trends and...well yea I was never optimistic this was going to anything other than what it is turning out to be. I allowed the positive vibes in November and some pretty epic looking long range guidance to influence my final winter snowfall forecast. I still went below normal because I had a feeling I just couldn't shake but I went closer to median v the truly awful results I was kinda fearing. I probably should have stuck to my initial gut feeling. Still time though, and luck can work both ways...all it takes is one really lucky event for the DC area to avoid a horrible fate.

So explain to me what longwave pattern works in that background state, when even in the old “normal” we needed solidly negative anomalies to snow.