Typhoon Tip

Yeah, it’s making a 3 to 5 inch event more likely

GFS looks like the NAM

It’s not really east… it’s tracking along the climate route if you look at the center of that mass - it’s really just that it’s weak and spread out therefore

Haha. Didn’t we just getting a regional wide 6 to 14 inch snowstorm last week.

Yeah... I was even going to say that the "N. Hemisphere" has predicatively superior regions over others - and that individual models will handle quadratures differently than others. In other words, the GGEM may be fan-fuckum-tastic from Japan to California and better than the GFS; the opposite could be true over N/A. (that's plausible speculation though - I don't know if there is any way in which these averages are smoothed, or not smoothed/normalized)

I'd say the "voodoo range" - statistically - begins around D10, actually ... but in principle, I don't disagree that there's a futility inherent to being very precisely deterministic ( to put it amusingly ..haha) when it comes to a 252 hour time range. But there are techniques - some are better at it than others ... - that give the D6-10 range a bit of an edge over N/S ( no skill). Having said that... fast whip lash flow tendencies because the same speed, makes it almost physically impossible to anchor a pattern in position

People will tend to trust their own anecdotal experience and dismiss a panned statement like this intones, without you citing sources just fyi -

I wonder how it will look after this ... For the record ...I suspect this 18z run is kind of bonkers overall - no trolling intended. I think we are headed for a reload interlude of yet unknown amplitude - but either way, I'm not sure we're sending 582 dm heights to the Del Marva to get that done. We'll see... But just J. H. Christ here. This also hearkens to what I've been saying ( for years really - ) that when the cold air shuts off we seem to almost spring loaded bounce into this outre warm plush across the mid latitudes - or tend to do so. It's been so reproducible over the last 10 years, regardless of whatever discrete or voodoo combination of indexes were doing corrections to unicorns, that I begin to think massive oscillatory behavior is the new norm.

As opposed to what, though? Not being a jerk just seriously, the options are missed super phase but miasma of snow in the air ( perhaps to moderate), or whiff. I mean we've seen either of those two impact portraits regardless of 12z or 18z or 00z or 06z, over the past 3 days... The only common denominator between all the runs has been velocity of the flow exceeding the phase rate. So that latter can't happen in time. I see this run .. yup, same schtick. There's plenty of time to manifest higher heights over western N/A ...so's we can slow down the flow and allow the dynamic interplay of these features back E, but... supposition: I also suspect some of the velocity issues are everywhere. The hemisphere is just having trouble shortening the Rossby wave lengths overall - in other words, longer ... not taller wave lengths are accessible.

Confirm intense squall in Ayer. Vis down to ~150' Est 50 mph wind gust (max). 37 to 27 in a matter of moments lightning up... duration was 7 or so minutes

https://phys.org/news/2024-01-global-ocean-temperatures.html

not saying either way ... just pointing out some aspects I'm noticing - Extending that it's hard to automatically assume the lesser popular/known guidance types will be typically wrong in this seemingly rare case.

This may be a rare scenario ( when speaking in terms of model performance/history <-- relative to...) that the Euro corrects toward the less conventional/trusted model sources. In fact, ...so rare, I wonder if that's ever really happened where a GGEM/RGEM/ICON blend successfully coup'ed That said ... after 3 consecutive cycles the GGEM had ticked more impacting... as of 12z, arrived looking more RGEM like than ever. It gets hard to knock such strident continuity; now < 60 hours, when said trend of the Can cluster has been there since late middle range. -when then also introducing the philosophical aspect I outlined regarding the explosive baroclinic boundary condition laid into place between ~ ATL to just SE of Cape Cod by this arctic boundary/air mass that slows down and stall along that axis... I think there is too much argument in favor of these guidance from both an operational technique, to concept Meteorology, to dispose these solutions in lieu of a Euro paltriness that has in fact been 'trying to avoid admitting it's wrong by hedging the event in silent intervals' I mean I'm not sure of any of this... sort of tongue in cheek.

LOL sorry guys. slow Sunday ... I need it, anyway. fun stuff over fixing legacy code all week - ugh.

Not saying it won't - ...just as is, the models that show this 'not in time' aspect are likely suffering from the discussion points at hand. But these are virtual projections. The models may be handling the flow over the continent wrong, too - so they could be too fast. there's moving parts to this..

It could. I'm really using thought experimental logic to explain what/were the limitations are. As far as "fixing" this thing? haha. Yeah. I think of this way... the heights over the S-SE seem to roll along by a different wave function/planetary forcing, and may or may not be in sync with what's going on over top ( above say ... 35 N). Here, I can draw a quick and dirty illustration to explain this pictorally This happening at varying scales ...etc, this is just a illustration to bring the point ... If you can imaggine this "Quasi independently" caused height wall in the S to be oriented opposite of that implied wave signature, than there is less compression --> less +d(v) in the flow entering, which then allows more curvature to take place sooner with less shearing... What the flow may actually look like, while the above is happening, doesn't necessarily reflect -

See - without even looking at this product, 1978 is in there. I'm tellin you guys - big big dawg is being poked. Not sure we can wake it up in time. With all this speed shearing and forcing this thing to open ... It's offsetting the time it needs to "couple" to the planetary curvature/Coriolis ( that's really what it is...). The dy/dt is the N-->S component velocity of the SPV piece. The dx/dt is the W-->E component of the S/stream S/W. When the ratio of these two are compared to the time constraint of the Coriolis parameter, ...I bet you dimes to donuts that needs to be closer to proportionate for determining phase proficiency. wow

Oh, I said that backward... let me fix that. The thermal wind vector increases, the velocity of the geostrophic wind increases, and thus Coriolis parameter can no longer force the flow to curve in time - the centrifugal ( g-force) over comes the curvature imposition of the Coriolis effect. That's what opens the flow - fuck. I correct that. The Coriolis parameter has time in the function... here, I just grabbed this right quick off of Wiki' The rotation rate of the Earth (Ω = 7.2921 × 10−5 rad/s) can be calculated as 2π / T radians per second, where T is the rotation period of the Earth which is one sidereal day (23 h 56 min 4.1 s).[2] In the midlatitudes, the typical value for f is about 10−4 rad/s. Inertial oscillations on the surface of the Earth have this frequency. These oscillations are the result of the Coriolis effect. anyway, it's simple - lower the god damn gradient so the Coriolis can curve the flow.

...I was also noticing that the final bifurcation of the western Canadian quasi SPV feature is actually taking place during today - so there may be a subtle modulation in what is really injected into the flow, being initialized into the grids today.

Interesting how persistent the RGEM has been ... And if getting persnickety in that analysis, it's even been adding QPF in small increments, while continuing with the same general synoptic layout of this event. It could not be anymore cut-and-dry case for being proven either right, or wrong. If it verifies even above 80% of its panache, it's going to be an emphatic winner. Anyway, this 12z run... if we just bump it's QPF layout 20 or 30 mi SE, HFD-BED ends up with 6+". It's high end advisory/low end warning snows. It's certainly plausible that the QPF is right and it's too liberal warming the SE of that axis, anyway... I mean this antecedent arctic boundary apparently means business. The NAM is also some 70% of that QPF ... just estimating, while having a similar synoptic evolution. Why for the QPF differences when the synoptics appear otherwise to be the same - some difference in physical make-up? I dunno. I'm leery of the NAM's NW bias at this range. It's interesting, however ...that the RGEM is sort of trying to peer pressure the NAM into taking the same drug. Haha. I'll tell you though.. pure supposition - but maybe these higher resolution models are "understanding" the physical initial conditions better wrt to this newly arriving and intense arctic boundary. It appears to slow down dramatically after arriving here... collocating with the existing thinkness gradient that extends ~ ATL -Va Capes to SE of Cape Cod. That's going be an axis of explosive potential, to understate it.. It would not take very much jet mechanics at all to activate a low pressure along that zone, and given the efficiency sharpness of the frontal/thickness packing, the UVM circuitry will be made more proficient. ... I guess what I'm saying is I can see a valid argument for higher res models doing what they are doing. Technically the Euro qualifies as a high res tool, as well.. which doesn't lend as much help to this idea.

I'm wondering if there was modeling error ( from 10 days ago...) wrt the extended range, and what's happening now west of this arctic boundary Quite the impressive morning array of obs expansive throughout the entire continental midriff ...with -20 to -7F, 2-m obs everywhere. I was looking at western Michigan ...everyone is 0F in a WSW wind having come across the entire ~ 50 miles of that Lake Michigan, and -12 on the Wisconsin side ...that's a typical correction from thermal input off the lake that happens in syrupy cold outbreaks. Then, of course hundreds of miles of brick earth negative temperatures throughout the CP/NP regions. That KC/Dolphins game ...ha I get it that it was signaled - more or less... I'm just wondering if this is a rare cold bust for a change, even if by a small margin.

Yesterday I was musing about the front edge being a single clap of thunder with a mix of small rain drops and big aggregate snow balls that mimic soft hail, going sideways under a rapidly advancing outflow nimbus belly, soon to flash over to the whiteout snow squall ...ending in 10 minutes. It's like if you went 2/3rds or something up the vertical column of the typical squall line in summer, and brought that region down and made that the bottom of the storm ... sort of -

Scott nailed it in his morning/brief analysis, using the Euro to describe primary limiting factors re the 20th system - it's actually consistent as an observation across all guidance, really. It's also been the case since the period in question first began to emerge in the operational versions. ..some 3 or 4 days going back (btw, the 20th was suggested via other means going back long prior to the operational model detection - ), and has persisted ever since. Just want to add some analysis/observations to that. From a broader perspective, the velocity of the field is there first, and is "why" the above factor has persisted. Why? The models have difficulty (perhaps a range -related thing .. I wonder ) constructing N-S orientations - it becomes a geometric problem in that higher velocity, when going around any curvilinear trajectory, induces an outward acceleration force that is normal ( perpendicular ) to the surface at every point around the curve. This acceleration force is centrifugal, or "g-force" as is often referred. As the speed of the movement around the curve increases, the g-force increases with it. How it effects the geometry the atmospheric circulation pattern: When the effect is large, it's because thermal wind vector component of the geostrophic wind equation is very large in higher gradient, and caused higher wind; that forces the curve to open up. One needs to compare equations ( mathematically ) to assist in proving this, but the aforementioned concept matches the observation in the field rather nicely. It's fascinating if one understands this. Annoying and invoking of chiding when they don't. I understand this... buuuut, unfortunately, the fascinating aspect is being on textbook display and is why this isn't already modeled as a 1978 redux. All the players are initially present. In fact, even the super synoptic indicators are flagging something incredible. The idiosyncrasies surrounding the negative interference via too much flow velocity, that is unfortunately not described very well in either the snap shot of identifiable features, nor these numerical teleconnector projections, respectively. 1 The PNA is rising slowly anyway nearing the period, but, all sources 'jolt' the index from ~ -1.0 to +1.0 SD in the 2 days immediately antecedent. That's a big signal from a super synoptic source - check 2 The -NAO corrects to neutral - this is physically expressed on the synoptic charts as the western end of the block collapsing S across the Canadian Shield; underneath this mode change, the 'SPV fragment and cold mid and upper heights are conserved, and threaten to inject an extraordinary instability into #3 (below) - check 3 The rising PNA injects(ed) some sort of intermediate and/or S/stream S/W which interlopes underneath all that in proper timing - a simple way of saying they are in wave harmonic/ or positive interference - check It kind of all smacks as a 'chicken vs egg' conundrum but it really is started because there is too much gradient through the total domain region in question - which for the purposes of this discourse is really from 140 W through 60 W. The flow is faster over the continent, because the continental influence on the total circulation of the hemisphere causes it to draw cold air down, which reinforces said gradient in perpetuity. The models have difficulty ( observational assumption ) in this area with acceleration being variable from run to run, particularly at the 'flop' end of 'the extended range hose times'. That's why I am willing to postulate further that range is related in this error. So... in simpler terms.. .the Pacific is attempting to for once serve us better by sending the +PNA --> +PNAP flex. It's there. Unfortunately...the models are constantly countermanding ... negative interference by said overabundant gradient problem. The flow speeds up... the heights are physically limited from N-S orientation... It's like this idiosyncrasy is competing - and what's interesting is that the models are actually creating both sides of that fight.

Hilarious! That gives me a perfect mental picture… “Cars sliding down to Zakim Bridge into the tunnel”

He may be subjectively right - if that makes any sense ... If we lay in 3-5" ( say), that's not really a snow "storm". But the other aspect is that it may be up the coast from the mid Atlantic latitudes, either way.. so, partially correct there, too.