Wxbear25

So? Discussing modeling, forecasting, weather in general shouldn't be looked down upon just because you're not getting snow, particularly when it pertains directly to the system the thread is about. I get being frustrated by the overwhelmingly likely outcome of the storm, I just don't think its right or fair to talk down to or mock people who are in good faith actively discussing aspects of the modeling/atmosphere directly pertaining to its evolution/modeling, etc. If thats not how you meant it to come across, I apologize, but as someone who has been doing directly what you were lamenting, thats the way it seemed

I think back to back is more rare moreso because storms naturally wipe the board clean, so to speak The Baroclinic zone shifts, strong storms tend to displace features that allowed the strong-storms to occur in the first place, etc. In this particular case, all the pieces are all there to allow the second storm to come, its just overwhelmingly likely that those pieces dont thread a small, but not non-existent needle

I think you're looking for "AmericanSnow" forums, not "AmericanWx" forums

Largely, yeah, though it continued tweaking ever so slightly until game-time. I'm working under the assumption we dont need a massive shift to allow these two pieces to divorce more cleanly than they currently are. Is it a hail mary? damn straight. Would I forecast it, hell no. Moreso typing a steam of thoughts as to how this system could theoretically work. Regardless of the final outcome, its an incredibly fascinating storm from a meteorological standpoint, and, to me at least, trying to pin down any potential variables and how they could potentially affect the outcome is alot of the fun of forecasting, even if its an insanity-inducing PIA lol

yup. Between the multitude of moving parts, the poor data-region the primary feature is coming out of, the potential spin-up of convective-driven vorticity east of the main feature and whether or not that can gain latitude and the overall anomalous nature of the entire setup, this would be the storm to catch people by surprise I'm more concerned with the upper level evolution, and I think moves from things such as the GFS are closer to producing here than it may seem, so I've not yet given up hope, but I'll admit it definitely is much more annoying than last storm where we knew we were getting hit, just trying to fine-tune all the smaller details. He're we're trying to fine-tune the entire damn system lol

The craziest part about this whole setup to me is how "close", yet how "far away" it is Normally when a storm is that close off the coast and heights rise downstream by 4-5 DM it means its coming closer or. Unfortunately for us, we're getting screwed by latitude more than longitude here

I said it yesterday, but personally I'm holding out until 12z Friday if only because most of our super-important pieces will be over the US at that point I'll still follow it, even if it isnt going to work out because its a fascinating system, and I've been telling my friends/family/coworkers I think its a closs-miss for LI for a few days now, but I've been secretly wishing I was wrong for obvious reasons lol

I definitely wouldnt forecast a hit for anyone outside of Nantucket at this point, but my hope lies in the anomalous nature of this whole setup. Speaking of the setup/// That connection between that departing ULL over the NE and our chunk of energy diving into the upper midwest needs to separate faster. Each of their momentums are screwing us in different ways, so I agree wholeheartedly with @dendritein his post last page The momentum from the western side of things drives heights lower over the atlantic ironically, since thats barbelling southward dragging our eastern lobe with it. This ultimately make it harder for heights to recover from over the Atlantic which keeps the flow from backing and turning more meridional. The momentum from the eastern lobe pulls the western piece more eastward, giving us less wiggle room. The best way for that problem to solve itself is for our western energy to end up further west than modeled, similar to what happened a few days ahead of last weeks storm, and then pinch-off earlier which would theoretically alow it to dig more toward MS/AL instead of SC while simultaneously allowing heights to build off the coast

Gonna have to disagree with you there, its mostly about that front-running stuff, IMO. You can keep the kicker exactly the same, if you can better incorporate the stuff around/north of the Bahamas into the general circulation instead of allowing it to stretch the circulation and flatten heights ahead of it, you'd be dealing with a massive storm much closer to the Delmarva. The way its modeled now, that front-running stuff is creating the weakness that the ULL escapes northeastward through The runs that showed hits and or very-close misses all share the characteristic that they orient that energy more meridionally than zonally

Yeah... this is one of the more complex situations you'll ever see, so anyone saying its definitely coming/not coming could not be more disingenuous lol From a pure synoptics standpoint you'd think "how could it miss" and then the ridging ahead of the low gets de-torched by little strengthening perturbations in the flow We're not at the end yet either way, my friends

im wondering how much of that is being skewed by a couple of rogue members. With that being said, ~10% chance of 24 hr QPF >1.00" over LI on the 00z run, as opposed to 0 on the 18z, so theres that

The energy that eventually becomes our storm is still over far-northern Ontario, which I cant imagine is great for data collection. Remember the last system, how over time the northern stream sourced from the same region ended up stretching more and more as we got closer to the event? I wouldnt be surprised if we see that occur here as well. That should be over the northern U.S. around 12z Friday, so personally im going to give it until then, even if we should have more info by 00z Thursday night

Its all gonna come down to how well the ULL can reign in any front-running energy ahead of it. The more compact the system is in the upper-levels, the more consolidated it will be at the surface and the further north it will get before eventually pinwheeling northeast these runs that end up going SE, you can see how the heights east of the storm "open up", so to speak, and fail to wrap back into the system. This is the energy spawning those secondary areas of low pressure, which prevents the system from consolidating, and also resulting in less moisture transport to the main low resulting in paltry precip on the northwestern side of the coastal. It can be seen quite clearly at 500mb vorticity at the hr 90/78 timestamps of the 12z/00z runs of the CMC.

Looks like it ends up between the 12z and the 18z, good hit for Nantucket looks like

I dont look at the surface until after I've seen the 500mb level through where I want to know the forecast for, but I can tell you heights are significantly more backed over the NE, which is what we want. Whether or not it does the job at the surface, dunno yet

The RGEM looks like it may want to play ball in its completely 100% reliable and for sure not innacurate long-range

NAM looking less sexy than 18z for sure. Worse ridge out west, more positively tilted trough axis in the east through 63

If that ULL digs far enough, maybe the next long wave trough can pick it up lol

It seems like it gets the ULL to the same latitude as the GFS and NAM between like Atlanta and Greenville, no? just not as strong with the feature

Yeah. Synoptically the 18z ICON and NAM look very similar in terms of positioning of the main ULL, but the ridging both over the West Coast and off the Eastern Seaboard are definitely lower on the ICON, so I’d imagine it won’t look nearly as good as the NAM would have extrapolated

I mean, I tend to agree, but was just playing it conservatively. it looks like the NAM is much more efficient at “catching” the energy rotating around the ULL and throwing it northward rather than letting it escape eastward Question is, is this a situation where the NAM’s resolution may allow it to better handle that smaller-scale stuff? Maybe What I do know for sure is that it being at the end of its run does it no favor for its accuracy scores lol

Extrapolating out I’d wager the clown-range NAM is a hit at least for at least eastern LI, SE Mass

I mean, if you want a snowstorm I feel like you want the NAM to verify at 500 here. Thats one I look at the 500MB pattern and think “how does this miss” Most of the other guidance I look at right now and say “how does this hit” I don’t trust those bowling-ball lows the GFS, CMC, and Euro have to produce since those are tough to drag northward as opposed to kick with more eastward force Of course it’s the 84hr NAM so…

GEFS took a fairly large step backwards it seems. Further south with the trough and attending surface feature

yeah, I think the QPF ticking down is moreso a function of losing some of the super-super amped ones, but on the whole they congealed pretty well further west. Now we just need to get to work on the "more north" part