psuhoffman

I dont think so, but its irrelevant the Euro and other guidance isn't as crazy so the GEFS is probably overdone anyways. But they all have a very healthy wave into Phase 8 and implied 1 after.

No way, lets blast the MJO into 20 STD phase 8/1/2 and enjoy a parade of 960 lows bombing off the VA Capes to the Benchmark.

People shouldn't miss the fact we have legit blocking right now and that is what sets the course of events in motion for the next 10 days. It's not the strongest block ever, and its transient and only last a few days but the block forces that system in the west to cut under it which becomes the 50/50 low that holds in confluence and the high pressure creating our snow threat next week. Without that block next week would be another cutter. Because the block breaks down...it still could be but it creates at least a chance. You can see the block is breaking down here but it did the dirty work and we have a perfect 50/50 to work with. A lot of our snowstorms come AFTER a block has broken down but it did the dirty work needed. Beyond this...towards day 10 we lose the 50/50 signal as without any blocking odds are it will slide out. Towards day 15 we see the signal for a 50/50 again at the same time we see some -NAO signal on both the EPS and GEFS. Given the monster EPO ridge it doesn't have to be a crazy NAO block. Even some modest ridging there can be enough to get a system to cut under into the 50/50 and combined with the epo pressing cold into the CONUS suppress the trough enough to get a system under us. But we need SOME nao help to get this whole thing to work. We got it this week, it was mostly unnoticed because we are torching with cutters but the posible positive impacts come next week. If we can get another period with some -nao we should get another legit threat. If we can get some sustained blocking we could get a longer favorable period. Today's mjo update still shows all guidance getting into phase 8 by day 10-15. Euro still faster then the others by a few days. The pressure anomalies on both the GEFS and EPS suggest a crashing SOI by day 6-10. This should favor a trough in the eastern US heading into late February and early March.

Sometimes the lag can be annoying... last year we had the MJO and SOI become favorable in February and the pattern took 2 weeks to really respond. BUT...NAM was a wrecked mess of warm air last year and so it took a while to get right, and then even once it did get right we were in a nina and had to watch a couple miller b storms hit to our northeast then a weak system get squashed before we finally cashed in with one good classic west to east system. That is kind of the MO in a nina NOT a nino. Some of the data diving I have done suggests that during a nina we are totally and completely screwed without a -AO/NAO. Since 1950 I only found 1 warning event at BWI during a nina without blocking during or before the event. That is why a nina sucks so bad...typically we can luck our way to snow without NAO or AO help...but during a Nina forget it. However...I also found that even during a -NAO our chances are muted somewhat. We need a pretty stout -NAO to press the pattern south or else we get miller b storms that effect to our north. 1996 was the exception because the blocking was extreme enough to cause those miller b storms to be southern stream hybrids and transfer south of us. Last March we finally got one of those when the blocking became extreme enough. During a neutral our results are good but still somewhat hit or miss with a -NAO. The thing is...during a weak to moderate nino a -NAO is like GOLD! We tend to get obliterated when we get legit blocking during a weak/moderate nino. Some of the nino's that failed were because we never got nao help. 1995 we got our one storm during the only real blocking period. 2007 we never got much nao help. 2005 had some blocking but it was weak sauce and so we had a few decent snowstorms but the big stuff hit new England. When we get legit blocking during a nino though...that is when we go on a snow blitz. ANd yea I know there have been some things about this nino that do not fit the mold but the stj is not one of them, the stj has been strong all year. I also don't think the lag will be as much this year as last year. So if we can get the forcing right by the 10th or so and get the pattern right by the 20th or so...we have time to sneak in a couple really good threats before time runs out.

Soi crash is still 5-6 days away. By day 10 it looks very negative. By day 10 convection is centered where we want and gets better from there. I haven’t even looked yet but just from this I would expect the long range to look good.

I don’t want people to think I’m saying this is a bad setup. A 1040 high boxed in by a 50/50 with a SW to NE moisture feed is a good setup. Unfortunately even good setups fail here often.

@showmethesnow one last thing not to like about the split wave idea...even if we get hit by wave one if it holds too much energy back it can cut something right behind it. It would be kinda bittersweet if we get 4-8” then it’s pouring rain and washes away 12 hours later. The more it holds back the more threat it ends as a rainstorm. Personally I find it hard to be happy with a storm if it ends with bare grass. Let me be clear I am not predicting that now. So save the deb posts. But I’m pointing out how I could see a fail here. I can also see a win if the high holds, or the energy ejects faster. I wish my fail scenarios didn’t happen so often though.

It didn’t do it this run but he is right that we don’t want the main feature holding back like that. We have better chances if more comes out sooner. Even a full ejection can work if it’s early. But if weak waves peel off and go to our south then the main energy comes across wed/Thursday that opens the door to being stuck in between. I think there was a storm like that in a similar setup in 2012. South of us got 4-8” from a front runner, our area got skunked, then north of us got 6-12 from the cutter. There was another similar one a few years ago in feb 2016 I think. DC got some but south 6-10 from wave 1 then wave 2 was central PA north. I was totally skunked. That’s the fail path here so I agree with Ji I don’t like any run that ejects a weak wave Tuesday then holds back the main wave to Wednesday. That progression can go sideways for us quick. I want to see it all come out Tuesday or at least most of it.

The two biggest fail scenarios are a full phase and the whole thing bombs up to our west (very unlikely) or the energy ejects in 2 pieces and the first runs out ahead of the upper level support and gets suppressed. The next holds back until the high departs and goes to our north. Imo that’s the worst fail option here.

Just extrapolate it

Lol

It snows and sticks in Colorado in May and they have the same sun angle we do. A-basin got 30” on July 4th one year. Yea their elevation helps with temperatures but that has nothing to do with the sun angle. It’s the dumbest argument ever. If it’s cold enough and snowing hard enough it will stick any time of year. It’s obviously harder here at our elevation to get cold enough the later you go into Spring but still...the bigger problem is temps not sun angle.

What’s up with that anyways? Even though I am in MD I realize I’m on the edge of this sub and my elevation combined with my latitude gives me a different climo. I try to keep my posts DC/Baltimore centered as much as possible. I like the discussion and analysis and there aren’t enough people here to have the same thing. I do pop into the PA sub sometimes but our sub has more posts in 20 mins than they do all day.

They will still say it.

Jb thinking it will get cold is a reason to be skeptical. I joked back in November that my biggest reservation was that my winter forecast matched JBs. I should have taken that more seriously. But I guess once in a while he has to be right just by blind luck so maybe this will be one of those times.

It was just 5-6” a week ago. There were times last month it was ~6”. Last year in March we got a few 6”+ looks and late January begins it sniffed out that epo gradient pattern would shift NW we had some. Back in 2014 and 2015 I remember a couple times we had 8” means. Of course 2016 from range was crazy. And several times the last few years during dumpster fire patterns like January last year and Much of 2017 and December 2016 we had 1” means. 3-4 is the average and indicates an average chance of snow which for us isn’t very good. The eps has been awful this year. No argument. But it doesn’t always show 3-4”. And it’s changed just the last few runs. 3 days ago DC was at 5”. The eps doesn’t have wild swings like the gefs. A move from 3” to 5” is significant on the eps. Doesn’t mean it’s right though.

Now that’s a signal you don’t see very often lol I’m sure the sun angle brigade will be along soon to put a wet blanket on that with “but any snow will melt the next day”

The gefs has had that look for about 6 runs now but no one cared lol. But it’s finally picking up on the mjo/soi imo. Oddly the euro picked up on it first but seems to lose it in the long range and the gefs day 15 looks more like you would expect. If even half the NAO blocking the gefs thinks is real it would adjust the eps into a damn good pattern like Bob said earlier. I am cautious about the day 6-7 storm. It’s a tricky setup. Doesn’t mean it has no chance, I’m interested but not confident yet. But I’m bullish after that we see more good chances this winter.

I’ve always just called that an epo block. It works better then a normal epo ridge. Still not as perfect as an NAO block but not a bad way to roll either. PD2 was a weird jacked way to get a hecs imo. I would argue November, the early December miss, and the January MECS were all pretty good patterns. The last two just didn’t last long. The January one is maybe overlooked because it evolved into a good pattern at the last minute and since the models overdid the suppression a bit until the last minute. But the analogs were warning us all week leading in with big snows littering the top 10 pattern matches and then we got that second minor snow too before the pattern broke down. I would agree it wasn’t a great pattern from range but ended in one in real time.

Well even if we didn’t have good reasons (mjo soi) to think it will adjust our way we know that trough is likely going to not be exactly where the eps says from 360 hours. So if it adjusts south any we are great. North any and we rain. 50/50 ain’t bad odds. I tend to think given those 2 factors it’s better than 50/50.

That’s not true. 1-2” is the background bogus fake mean in a shutout pattern that happens from the 10% outliers. 3-4” is average in a typical “it might snow but probably not” and when it’s 5-6” it’s usually a good pattern and we have better than climo odds. Keep in mind that still might only be 40-50% so often it fails even then. Snow means are bad ways to judge ensembles. And that’s just a typical quick rule. And obviously since guidance has sucked at range this year and typically by having a good pattern that wasn’t real the fail rate this year is much worse than average but since some people here don’t know when your kidding let’s not pretend the eps always has 3-4”.

If the opposite trend with some blocking shows up now that the mjo and soi seem to be cooperating, if we can just get some NAO help it would suppress that whole SW to NE trough and we would be perfect. Doesn’t have to be a prolific block just some ridging would do it.

Loved the surface didn’t like the h5 on this run.

It can be more then that...there are rare times I’ve had 10” when DC was all rain. But that’s more typical in marginal surface temp situations. In these type storms typically if I want 10+ I need DC to at least get 3”.

It’s too soon to get into details. I still have a vested interest in 95 because in these setups if DC (or at least just nw of it) can get 6” there then I can really get crushed. If it ends up being an hour of snow to rain in DC I might get 3-4” up here but usually not more then that. There are exceptions but if I want really BIG totals I want at least the DC burbs to get a good thump too.