psuhoffman

Well be careful with that... because a NS dominant solution would likely not end well here. Almost all of our big snowstorms need to be STJ dominant. That is why there is such a huge difference in snow climo in la nina years between DC and NYC. We are simply too far southwest for NS systems to work. They develop to late for us 90% of the time. I agree this time period has a LOT of potential, but if you want the mid atlanticn south of 40 to get in on it there will have to be a trend towards a stronger STJ component to the threat.

There is one there, it's just too weak as of yet and gets dominated by the NS making for more of a miller b screw job setup. BUT...that wave wasn't even picked up at all until recently. We just need a SLIGHT adjustment there and boom. The pattern has been screaming for that window. The longwave setup is absolutely perfect in every way. We just need a somewhat healthy STJ wave to come along during a 48-72 hour window and it will likely work out. 12z GFS/EURO were very close just not quite a strong enough wave to get it done. But its so close.

They lit up like a christmas tree

I prefer cows fart but go ahead

This one does not necessarily have to trend north. There is a TPV sitting right on top of us. Depending on how that wobbles it could even suppress the wave further. It's a chaotic situation with a ton of energy pinwheeling around the vortex but it's one where its not as sure to correct north IMO. Last time I was very confident in a north correction because there was marginal cold, no blocking, nothing to stop the mid level southerly flow, and the NS was way out of the way. There was no mechanism to suppress anything. This is a different setup.

Yea that's been the window with the most upside all along.

Euro has the same issue as the GFS. Too NS dominant, not an amplified enough STJ wave, late phase. But 24 hours ago none of the guidance had the wave at all so I'm not worried about details yet. Were talking about the wave after the wave after the wave here. We need small adjustments to get a big snow from that look.

That's the period I like best. Doesn't mean I'm not rooting for snow from the 16th or that it has no chance...but the upside if a wave can come along in that period is much higher imo.

I am not reacting too much to anything until we see things settle down run to run. FOr now guidance is still shifting all the vorts around each run. BUT...the one thing I liked most about this euro solution was how it gets a piece of the TPV out ahead of the system creating a more suppressive flow. That opens the door to a more amplified solution that still ends up frozen for us. If that progression ends up the correct one we have wider goalposts.

For this year... But really does it matter...look how ridiculously different the H5 is from last run. This is NOT close to a final solution and wont be for a while with all the moving parts behind the bomb system this weekend. So whatever it show's doesn't really matter yet. But I guess the fact that different solutions both lead to snow is something to take away, maybe we have a wider victory path than I thought.

This is true if you judge every pattern by the duality of "Snow or no snow". This is subjective of course. IMO there are many different patterns and frankly most of them don't produce snow. And even the ones that do dont always produce snow. We need a good pattern and then we still need to get a little lucky. If you pull up the mean longwave pattern its most definitely been opposite what it was prior to Xmas since...we just have not got lucky with the snow part of the equation. Mostly its been too warm.

That is the one with the best pattern support. We just need a healthy STJ wave to come along within that 2 day window. GFS almost pulled it off but the energy balance we needed was flipped on its head...too much NS not enough STJ. Flip that and it would have been a big storm IMO.

GFS came really close for the 20th. Too much NS not enough STJ. If the STJ wave was a bit more amplified and dominant the setup is there, and guidance is finally starting to see it, for that period.

I've had 50" one time in the last 8 years. But ok. I am NOT talking about what we need to get a HECS, that's not on the table with this setup. I am talking what we need to get a decent snow. 3-6" maybe. Not sure what you mean about yesterday, I've always said we needed an earlier phase but also a better outcome in the 50/50 space to offset, without that our window is very very narrow needing to thread the needle.

I can leave and you can start 17 new threads and it won't make a difference. None of this controls the weather. You know I'm right. Maybe things reverse today, but even the euro has been trending towards a messier later phase with a more progressive wave initially. We are pretty far southwest for that to work out, places northeast of us have way more time for a system to come together. We've played this game so many times, you know exactly what the most likely outcome is. IMO we want to see 2 things...we need an earlier phase so the system is organized by our latitude not just getting its act together...but then we also need a better trend in the 50/50 space or one of those SW's in the flow rotating around the main vortex to create some confluence on top to prevent that earlier phased system from cutting. If we get both of those trends we can get this to work. Late phase, late development, storm misses us mostly to the northeast. Early phase, no confluence storm cuts. We need both those things.

I know, and every once in a while things don't follow the "normal" outcomes, but we both know how that kind of synoptic progression with a late phase system starting to amplify right at out latitude usually works out for us. But its been so long since we had any snow we also know that everyone is going to latch on and hug any run that shows snow like their life depended on it only making the trauma that much worse when what is most likely coming happens.

IMO they are in the process of meeting in the middle from where they both were 48 hours ago. That should end up with us getting some pity flakes while just northeast of us gets a blizzard. We haven't had one of those in a while, time to feel that pain again.

The universe

DRY. BONE DRY. There was absolutely no precip at all until Feb 24 and by then the pattern broke down and there was a western trough eastern ridge and it was a cutter. That mean was from the first 20 days of the month and it's why we don't actually want a huge PNA ridge if we have that level of blocking...it was dry for weeks on end.

Can't figure out why

Just throwing this out there... we have been in a hostile cycle of the pacific and atlantic for the last 7 years, one that rivals previous "bad periods" with similar mean long wave patterns over a similar 7-8 year period. But this was HAS been like 25% worse. I know for the last year and a half of winter we've had absolutely no snow but in the larger 8 year period we're frustrated with we have had some snow. But during that time we have also had numerous "perfect track rainstorms". Yes those were always a thing, but IMO never at the frequency they are happening now. So if some of those had been snow we aren't in this 700 day snow drought right now and the last 7 years are more in line with previous bad periods. It's probably just that simple.

I have referenced that period in the 1950's as the closest comp to this...but pointed out this is worse, and I think that's where warming comes in. That period you referenced BWI averaged 13.3" with a median of 14.1. The last 7 years BWI has averaged 9.9" with a median of 10.9. Both were comparably bad periods and similar to the averages of those periods if you normalize for warming and our lower snow averages now but that just proves my point. The stats are similar for DC. That period in 49-57 avg snow was 10.9" with a 10.2 median. Now DC's avg since 2016 is 6.8" with a median of 5.4. This is worse. But what is really scary is that every previous snow drought that was somewhat close to this was bookended by epic snowfall periods. For example that period you referenced in the 50's was preceded by 8/9 years above 20" and followed by 4/5 years above 30". So, unless we go on an absolute snow heater VERY SOON...things will start to become absolutely unprecedented with no previous period that comes even close in comparison. You are right at this moment there are a couple previous periods that while not as bad are close enough that you could make the argument its just random. But if this drought continues a couple more years that argument becomes impossible.

Gfs finally shows something in the window the pattern actually most supports snow.

You’re right we should have been talking about all the snow we’ve been getting instead.