Typhoon Tip

The signal for the 27 .. 29th has been there almost as long as this one currently being monitored, but it's been more so in principle than practice - meaning hinted, but not coherently shown. Some of the guidance is closer to doing so, but like Superstorm93's post is close but still just a hint. My take on that is that the gradient is too much. The N/stream would like come down and subsume phase type, but the lower latitude curvature has too many isohypses and the wind velocity is out pacing - it's complex but it can't sync up that way. ...For the time being There also another signal around 2-4th of Mar.

We had that at 00z actually ... I posted the charts to demo page 7 or so

This isn't the thread for that but ... be leery of that assumption. The correlations heading through March for -EPO may not be the same in March as is such in D J or F - just be warned... The wave lengths overall begin shortening pretty coherently from Mar 1 to 30 ... That means a -EPO block may not transitively force a favorable look this far away ... March is a spring month that by virtue of our geography ... we've always claimed as a winter affair. But, that's bit of a circumstantial ownership. Some years simply don't product in March ... In fact, that seems to be more common since 2000, ... definitely since 2010 - even though there's been some blue bombs too. There are other aspect more circumstantial to now ...The larger hemisphere's circulation mode is only vaguely coupled to the La Nina base-state. The MJO has been for the most part ... irrelevant this season. It's attempted to move from Phase 7 ...twice, and twice failed.. .bouncing around for 10 days along the interface between 7 .. 8, ultimately deteriorating it's momentum to nothing. This time, we have a wave momentum that is strengthen back over the India region, which is correlated to the La Nina - the two may together force the atmosphere to "re"couple to the La Nina. It's unclear what that will mean for pattern, when combining that uncertainty ..with the seasonal relaxation stuff above. Bottom line...there's competing signals here.

Machine guidance taking a hit today ... Classic spring nape job on MET, even though it's only Feb 20 ... But, kfit, kash, kbed... were all 49 to 50, and are all presently 55, 55, 54.. probably good for a tick or two yet

It's interesting ... that combination of AN snow with AN temp - it's fitting that Phinny is extolling the frustrations of a dwindling snow pack. I guess buried in the averages of +5, there was sufficient melt events. I mean, there's lots of ways to get numbers that elevated... Persistent nightly lows being elevated. Or a couple of isolated whopper warm spells... etc... and they melt more(less). Whatever the cause and method of assault, having above normal snow result in below normal pack, is an interesting achievement - particularly in any context that includes the word Maine -

I'm curious... that far north and climate specific region, that would be a helluva climate anomaly to remove snow all the way down to earth entirely, before March 1. I gotta assume already your snow is probably corn variety? As you know.. that by virtue of density is going to take more energy to melt - like cold in the bank. I think you'll have some left. Either way, the anomaly is already logging - You know ... just a "hot" take on matter. To me it's really spring already. I mean this is what happens in spring, early spring life in New England - you get these warm ( relative ) days, followed by snow chances. And it's probably a kind of sneaky climate change aspect, because we would've gotten this more akin to March and April some 30 years ago. But in 2022 and a couple of decades of hockey-stick CC acceleration ... it's starting to happen in February and March's. So shift up. But it's also not black and white... Just as other Febs and Mar had some fantastic warm affairs in transience over recent years ( as part of this CC suggestion - ), the variabiility that extends back into the cryo realm is still in play. We could be 80 twice and get a blizzard on March 25 for a spring diabatic blue gem monster that pukes 52" along the spine of Whites... and still verify a +6 F month.

Yeah, that looks like orographic forcing. You live by mountain life and you get the life sometimes I guess -

Oh, I didn't see that Brian - ha. Yeah, that's a bitch... In fact, that's settling S... I wonder

I think today may mangle the guidance some on that... What I mean is, we're likely to over-achieve by a little, with this unabated solar going on through a modestly mixing +5 C at 925 mb ( assuming that's the BL height, but it could be a wee-bit higher...)...etc..etc... and MET was ( last checked - ) 49 at ASH ( which is what I use considering it's like 10 minutes as the crow flies from Ayer). We are already 45 at enough home sites/Wunder network and by sensible appeal to go ahead and assume we challenge that high pretty much by noon already. Digress... but this air mass may factor in the the BL mechanics of those guidance when we initialize later today - interesting to see if that happens. They are in situ, so if the initializations are cooler than is actual, it might be a red flag that this is a rare scenario where wedging in SE NH actually fails some.

Update: There's a limit to how far N the lower tropospheric reflection of this mess can track.. The 06z operational GFS is just about pressed against that proverbial wall. This is not an extraordinarily, mechanically powerful surface reflection/cyclone. It's moving up to a position roughly ... mid/C-E Pennsylvania, and at that point the BL resistance will physically impeded 1012 mb and cyclonic forcing from penetrating any further. That is why this is forced E ... and these annotations further below, showing the oblong low structure S of LI ( really the "quasi Miller B" behavior of this thing ) as 'path of lesser resistance'. The 00z Euro arrived ....other than very minor differences ( thanks Pivotal ), the projected 12z Friday position of synoptic features ( and assorted artistry in ptypes and what-nots), essentially line up beautifully. This is a well-formulating consensus here ( now watch it blow up in the next run... lol) I also stress that we tend to hyper focused on details from run to run, because IMBYism gets in the way of objectivity. Noisy moves in run become 'large shits' to the observer. But outside our jilted realms abandonment apoplexies ... at D4.5 ( 00z run)? -these are purely acceptable difference and a very good agreement here: Also,... I pointed out a couple of aspects that still persist in the guidance as of overnight.. This is perhaps a unique'er SWFE than the "climate SWFE" or typical model for those. This is bringing an usually deep tropospheric ingested air mass from the subtropics. The overnight PWAT anomaly product (GFS) maintained an inflated swath pressed up against the lift axis of the boundary ... sending that upglide. That, combined with the intensity and 300 mb S lateral exit jet region situated over central/NNE, might give this a vector toward over-achieving relative to said SWFE model. It's admittedly speculative ...like all prognostic 'art' ultimately is... but it may explain or partially account for these 10+" numbers we're getting persistently graced with in the model galleries.

Wouldn’t call it a jump myself. In any case it looks like the band between the pike and route 2 would get a lot of snow in a short period of time. IP CT/RI

Oh..I see what Will's saying though. Yeah, the GFS could afford to move that maybe 100 mile N of that primary to quasi M-b on this 18z run. It wouldn't harm ( very much..) the ptype of the Euro ( doing some cross guidance comparing...). But the 18z could easily just be noise.

Hopefully sobriety from moderation ...as in, clip those discussions and send them over to the banter thread ? god it's not even interesting for f sake

We're hyper focused ... I mean not you per se - but the variations among the guidance' is really not that great. But when ptype bands get very compressed along the x-coordinate, folks tend to magnify the difference between model's a, z, 1 and 3 ..etc, like they are huge.

I can certainly understand the reticence there ... if for no other reason, seasonal trend to bang butts within an inch of sanity just before beginning the butt banging.... heh But this is maybe the first event this entire cold season that featured a major polar high drapery sitting over top like that. I mean, already there ... prior to this baroclinic bowing back N beginning at 72 hours... It's not like moving in as the high is moving in(out) and we're dealing with races. Unless that changes appreciably in future guidance - which can ... yup - for now, we are not driving a primary to NY state with that +PP/BL resistance in place.. And it's dense air - it's in the single digits in Watertown NY (GFS/Euro) next Friday at 12z ? Mm... hope... this is not going west of the Hudson. Physically can't do that ... to mention, the confluence is there anyway. If for some reason in hades all that and that high suddenly correct tremendously well ...okay - not much we can do about that. Anyway, the actual cyclogen mechanics are weak in this. But the BL resistance is very high. So that primary dying and the quasi Miller B translation is really just response to not being able to move a weaker circulation through the dense cold air. It's correct relative to its own synoptic metrical layout.

Similar down this way ... Nice sun illuminates the south facing rooms and then you step out there and immediately step back in.

Yeah agree... Like Phin was just saying too, this is kind of an easy assessment frankly ... I mean, as it stands now - doesn't mean things can't change, of course. But this has really been, for all intents and metrical observances, unchanged in the guidance for days. Literally, ..for some 12 cycles, other than the Euro coming S and the GFS coming N... those two principle aspects have been there. a .. Healthy PWAT transport goes into over running mechanics b .. Huge evac jet above mid levels to enchance upglide lift ( a + b )/2 = *at minimum* hitting the standard model hard, which yeah ...that's 1/4 mi vis inside of 20 minutes of onset and your good for 8" then apple crisped on top... But because those two metrics appear somewhat anomalous, that connotes a bigger upside if they continue to model as such - we'll have to see how the week goes. The other aspect ... the antecedent air mass is quite cold and back build by that nicely placed polar high. This isn't wet snow.. it's like snow to dry sleet where that happens, then freezing glaze over top..., then straight mist below a pinned warm/stationary front.

What's it like up there right now... ? I got 31 F with 20 mph biting useless cold. But a very impressive cold roll-out ... we may decouple tonight, which may hinder tomorrow, ... but the sun is higher angle. We may mix out and bounce to the low 50s ...maybe mid 40s up there. Even up there, this could be an impressive 48 hours of departures en route, perhaps more anomalous at night once that happens. May be a question for the other thread - but Tuesday's system reminds me Friday's, only happening 500 mi se/track

So we all have experiences and personal analogs in mind ... it's part of the speculation game at this range. I wanna accentuate the notion that this is transporting a richer PWAT loading from all the way down to the Yuk Penn and adjacent Caribbean troposphere. It's 925 thru 700 mb deep layer of what probably ends up a higher PWAT air mass, S of the baroclinic axis, then is getting lifted up the warm frontal slope. Where ... it runs up underneath this 300 mb tube of escaping jet raging like an experimental outgassing at a NASA propulsion demo - Ah... hate to bun it from this range but that doesn't signal a problem with amounts of ...whatever falls. This has had that basic machinery for days of modeling now really. It may be banded, but it'll be moderate pan-dimensionally socked in, with thunder/snow bands near the sleet interface on dual pols

Tomorrow we may just be drunk with nape juice... wow - That has MOS bust written all over it. Which ...heh, we're not talking about a 6 on the seismic scale of busting when we say that, but at this time of year... high-ish sun angle with light wind over a brown pack-gone earth, and cold air actively en masse in the process of rolling away ... I could see it 52 or 53 type balm with warm sun, not being shucked away by a chilly wind - faux warmth ftw.

Not to yank my own chain but I mentioned that in the other thread ...that's a bigger meridional signal when combining total metrics for extended risk assessing... ( imho ) But we deal with this one first... well, technically, Tuesday is first. It has a windy squall threat again, with some ice for Brian N... but, both Tue and Fri are part of the same total synoptic evolution... After which, that sets up way out there... I think that real principle, but as that suggest we are not molding any forms just yet.

GGEM really has been quite striking with that front side/IB signal - more so than the other guidance. The GFS structures it's frontal positions and jets ( multi layer) in such a way that it could easily be as robust as the GGEM, but is probably lower in total QPF - I'm est - just by eyeballin' the art charts... I mentioned this goop at the onset, but my primary concerns are the source/origin of the deep subtropical ingest into the TV baroclinic wall...then, as that overrunning axis lifts to climo position S of LI ( assuming it stops there lol ), it moving into a position where the polar side is collocated under a very powerful 300 mb exit region/UVM mechanics. Strikes me as opportunity for QPF 2nd guessing... but we got the week to iron it out.

Yup ...all apologies conferred ... I looked for a thread this morning and did not find one re late week. I did mention recently I was intending to start one if I did not see one by this morning... I looked for it, didn't see it. May have been a timing thing - both doing it..

Oh shit -- sorry. You didn't have to do that. I swear I looked - I did not see a thread yet. I did mention the last couple of days I was intending to do so but I kept getting pulled away. Ugh. Last night it was late ...too tired.. so I suggested somewhere pg 114 of the Feb tread that we should fire one up and that I would if someone else hadn't done so by morning... I just didn't see it I guess.

Complex hemispheric mode changes appear to direct a winter storm across New England; time concerning is very late on the 24th entering SW areas.... but mainly spanning the 25th for all. This even is > 50% likely to occur. Short version of important characteristics: -- "Day 5," some latitude in these distinctions is obviously required -- large spatial dimensions and nuances in the system morphology as its bag of tricks evolves through, may mean a longer duration event relative to the speed in which this thing will be smearing along. This may touch a lot of the region. I would not trust QPF limitations due to mid level mechanics - more belw. -- first as an overrunning stripe with probably icing headlines in the MV, expands along E-W axis over late Wed thru Thurs throughout the OV. Very proficient QP band with snow/mix/ice/rain, N-->S, will likely be situated from OH-MA overnight Thursday night thru Friday. -- relative to synoptic mechanics, expect > normal/climo qualitative precipitation, which could even go above QPF. This if for two reasons: I wonder if PWAT products are entirely correct - this seems it could actually be more laden. The 850 mb trajectories are deep subtropical origin in the Mon/Tues. The other aspect is that as this GOM miasma is foisted N and lops over into the isentropic lifting column on the polar side of the boundary, there situates in tandem a very impressive lateral exit region of A 300 mb jet that spans the entire distance from the eastern Lakes to the lower Maritime. That would really enhance UVM potential and perhaps situated banding/meso embedded in a ...well, getting too detailed. That 300 mb jet, and the general concept of bringing a "potentially" hefty PWAT air source into its lifting interface has really been on the guidance' for some time. -- It's 5 days away, notwithstanding... that said, ice south... mix pounding could results near somewhere between lower CT-RI to the Pike, but the particulars of total synoptic metrics as they situate in the charts ( for now) this is probably mainly snow from ALB-BOS latitudes. subject to change/get tuned... -- In all ..what is likely to be in ballast, characterize -able as an overrunning ( proficient one at that!) event, there are hallmarks in the idiosyncrasies that hint at weak Miller B/quasi in form. There is even some suggestion of lag back CCB, albeit week, postponing the storm ends Friday evening for eastern regions. subject to change/get tuned... Other concepts: We probably should not ignore the nearer term Tuesday-Wednesday event entirely. Both it and the following system in question are rooted in the same larger hemispheric scaled changes. As the onset of a -EPO then wave propagates into the +PNA mode, ...that total behavior ( spanning typically a week to 10 days...), tends to first shorten the wave lengths over the downstream continent. Brief primer: The way that expresses, ...a tall non-hydrostatic height or closed ridge nodes bursts over the Alaskan sector. Immediately downstream, the wave forcing nadirs flow out W ... --> heights rise over the SE/Gulf/SW Atlantic. The -EPO ridge/block's gestation then relays into a new height burst ... usually over the SW Canadian latitudes. The original -EPO either neutralizes, or a new one may take shape ( like 2015!) but there is a time lag between the EPO magnitude and the subsequent PNA. The 00z Euro demos that total evolution with superb finish... In fact, there's a conceptual signal from multi-guidance for more of a meridional storm event .. between the 27th and about March 4 out there, but... cross that bridge. The two systems this week, Wednesday then Friday ... are really like the same event ... only differentiated by their trajectory. The first is follows the above template by tracking through the Lakes. The latter system, by virtue of the -EPO --> +PNA, repositions the mean baroclinic zone farther along a S-E axis. These large scale changes can take place without Wed or Fri systems. They seem to be like 'going through the medium as the medium is changing' In fact, they have been presentable in the various ens systems, ... predating these index explosions were seeing now as having high confidence. But, the mode changes didn't 'damp' them out as they occurred. It's really been about re-organizing the circulation and conserving them in the field. Kind of interesting ... if exceptionally dorky LOL.