psuhoffman

For northern MD crew. I was holding out some hope that 2 things could save us. A sneaky h7 associated band on the northern fringe and maybe getting a couple inches then ice from wave 2. Both of those hopes are fading. The h7 forcing is going north of us. It’s very disconnected from the main moisture feed, very similar to Jan 6. This will limit that bands effectiveness but could mean a 2-4” surprise for some places up in central PA that aren’t forecasted to get much snow at all. But we are likely stuck in between again like Jan 6 only worse, I think there is more dry air and less healthy moisture transport with this one. The second option doesn’t look good either. The euro showed the mid level winds ahead of the amplifying second wave to be more s-n which eradicates the mid level cold faster and doesn’t allow for much WAA associated precip to break out ahead of the low. You need resistance to get lift and precip. If the warm just bullies the cold away you don’t get the lift. The gfs and NAMs were showing a more SW-NE wind trajectory which lead to more cold resistance and a nice WAA thump snow. Alas they caved to the euro. My best guess for us is 1-3” from wave 1 and then maybe a little sleet and freezing rain to start wave 2 before it all gets washed away. If the coming period is what I expect our area should have our more typical geographical advantages in a more amplified pattern.

@Maestrobjwa but I think this time will work. This winter has been colder. The pacific base state isn’t has hostile. Look at this weeks it’s snowing in what was a torch pattern the last 8 years usually. So it should work better, if it doesn’t…uh oh.

Well let’s be clear what we’re talking about. There is always some ridging in between waves. That’s basic wave physics. Trough ridge trough. What he is calling the SER linkup is just the heights/ridges in between the troughs getting too high. In other words too warm. It simply a function of it being warmer. What 20 years ago would have been white or a shade of blue is now red on that plot. What that could mean on the surface is as the wave/storm approaches the antecedent airmass is now 35 instead of 30. That resists the WAA ahead of the wave less and pushes the thermal boundary NW and now 95 is on the rain side instead of snow. But all that is a fancy way of saying “is it getting too warm for that setup to work anymore?” We could debate how much of that warmer issue is from warm Gulf of Mexico and Atlantic SSTs or “you know what” or a decade pacific cycle but the question remains “in the current thermal base state does that work”. My answer is it better because those plots show exactly how we get 90% of our big snowstorms. Again progressive waves are not going to replace that part of our snow climo. Baltimore is not getting a 30 or 40” winter or a 20” hecs from a epo progressive wave pattern. That isn’t the path to our big snowy winters or storms. Yes it’s concerning this linkage that he is talking about keeps happening for the reason above. We NEED that to work for us. So I’m going to keep beating my head into this wall and praying blocking starts working again until it’s been proven 100% if can’t and at that point I’ll put my cap on the wall, hang up my coat and bid you all a fond farewell and check out for the last time and simply wait a few years until I can move to Vermont where blocking has still been working lately! Because in the end I don’t really do this for a 20” winter or a 5” snow. I track to try to get those 50” wingers and 20” snows we historically get a couple times a decade. And among the way I’ll take those 5” scraps as consolation. But if we can’t get the real goods anymore this will just be frustrating to me and for my health I’ll stop doing it and move somewhere that can still get what I want.

Because it wasn’t north it was just faster

Thing is even the runs lately that move that fgen death band north don’t help north of 70 at all it just tightens the gradient. Models seem to be locked in that the dry air wins lie up here.

Hmm the FV3 looked awful for MD and I wrote off the GFS since it usually is pretty close.

The low is 4.3 miles north of 50/50

You’re thinking of March 2017 that was ruined by a lakes low.

Second highest east of the Appalachian trail. Get it straight.

Sorry I’m still hung over. The range is 2-5” for the Baltimore area. Say inside the beltway. More south less north. But the difference might not be 2-5. If the 5 is right for the south maybe 3-4 north. If the south gets 4 the north side might be 2-3. This is way too specific but if you want a range for like Towson maybe 2-4”

But why is your bar a HECS? Those are super rare. If we get a 6-12” snowstorm across the area that’s a win.

Why do you keep talking about March 2018 as a fail? It gave us one of our biggest snowstorms since 2016! generally 4-8” across the population corridor with 8+ north of 70! And had it been a couple weeks earlier that storm would have been 12+ across the whole area. That block didn’t develop until the very end of Feb. The storm hit 20 days later after a few misses. This block is developing around Feb 15 so if the same progression repeated that storm would be March 5 and a 10-20” snow across our area!

Unfortunately wave 2 is coming in line with euro less snow so the bust option for northern MD if a south north split seems very likely. I’ve shifted my focus back to the long range.

We seem to do better when I’m skeptical so…

2-5” in Baltimore north to south. Not much of anything up here, maybe 2-3”. I might add some wave 2.

I’m telling you when the HRRR is dry and under amplified sometimes it’s onto something. Not always but I pay it more attention when it’s doing that then when it’s wet and amped. Also I don’t like the trajectory. When waves are projected to be this west to east at our latitude on guidance 24 hours out make up all the times I can remember when things sunk south at game time. The early March 2014 storm was the kind of that. Took a 6-10” storm down to 3” across northern MD. I know the trajectory is just a symptom of the true cause, wave that’s not amplifying enough to overcome the cold press but I’ve found guidance tends to underestimate the northward progress of the moisture transport when a wave is amplifying and over estimate it when it’s not and the trajectory is a good simple way to see it. These things aren’t universal. I’m still watching. I’ve not given up. But I don’t have good vibes. ETA: this is for MD north of 70. I think DC is fine. I’d be excited if I still lived in VA.

On the day of those storms yes numerically the NAO was neutral to positive. But there had been blocking and I consider the loading pattern days before more important. Second most don’t consider the nao by the numerical metric. If they see ridging near Greenland over a vortex under it near 50/50 they call it a -NAO, but numerically it’s actually a -AO. But I’m not interested in a semantics argument about terms. My point is that’s a good pattern for a snowstorm. I don’t care what we call it.

Yes but there were extenuating circumstances. First of all the boundary ended up set up about the same place a lot. And it was just luck that it set up where it did. I was up in central PA that one year and got a lot less snow then Manchester that winter. It was just dumb luck the waves went where they did. Also there were two very amplified storms that season in Feb and March where we jacked up here. But compared to the mean I won’t do as well up here over the long run in an epo driven wave pattern. If that was the pediment pattern every winter for example (using years with that predominant pattern like 2009, 2018, 2022) the avg snow for here would probably be like 26” instead of 40 and the avg snow for somewhere like where @CAPE lives would be like 18” which might even be above the overall avg. Yea being NW would help some but not nearly as much as it does in a more amplified blocking pattern! This area can go over 80” in a winter, even 100”! But most of those years had blocking and amplified storms not progressive wave patterns.

Chuck, first let me say you’re right about the numeric NAO, because of how they calculate it (which most don’t know) that’s probably a neutral NAO. But everything else I’m like ???? First of all that vortex is a hair off from 50/50 and because of how the heights curve on that map it’s more east not north of 50/50. If you go back a day it’s centered right over 50/50. As it is with the wave before, but it doesn’t matter because there is a huge SER that’s not had time to get beat down due to still hostile pacific forcing. And if that 50/50 location doesn’t work then now did this or this happen? The Atlantic vortex was in that same spot for two of our biggest HECS storms.

The pattern is locked and loaded. But now it’s time to cash it into snow on the ground.

Besides the fact I’m a big storm chaser and epo driven progressive wave patterns aren’t that… I also probably hate them because I moved way up here to get more snow and those patterns almost eliminate any advantage being NW gives you. It’s just luck where those waves traverse west to east and it’s typically cold enough even on coast as long as you’re north of the boundary. I’d love those patterns if I lived on the Delmarva or the northern neck. For them a wound up coastal can end up problematic because it’s hard to stay on the cold side closer to the coast.

not everyone lives where you do

I should specify I was specifically looking at MD where its DAF

It's just anecdotal but over the years I've noticed something with the HRRR when it doesn't match up with other guidance...when its more amplified/north/wetter than everything else it almost never is right. When its less amplified or south/dryer...it sometimes is right and the next run of other guidance moves towards it.