Typhoon Tip

I don't know about the 'big boy' heh... but yeah, I added to that post and discussed those Euro runs

I'll tell you, this is near the ceiling for 500 mb mechanics in a negative tilt. Look at that 150 kts leaving the Del Marva, placing SNE right in the cross-hairs of the left exit region - meanwhile.. .the 300 mb level winds are anomalously strong with hints at entrance region situated over NH/ME Whatever the QPF is on those intervals from HFD to CON you may as well go ahead and assume a meso band or two destroys that estimate. I mean ... this run in a vacuum. I have to tell you though, that is the most powerful S/W ( seems to almost be two in there possibly caught in bed together ) I've seen in quite some time passing over that particular region. 150 f'n kts. That right there is how you overcome the Miami rule - turn the S/W itself into a comet impact. Also, what's interesting here is the lack of S/stream in this lead up. The Euro had more ...but utterly abandoned the N/stream on this last 12z run... It should be Noted that the Euro at one time had a mid 960s mb juggernaut near the Islands... I am thinking about this GFS run ... 'cause, that's what dweebs do. heh. but, if we were to introduce a S/stream (more so) into that sort of junction ... yeeeeeah

Not that it means much bur the operational position is on the western limb of that spread - so tfwiw ... it may be easier to ask for it to slip E than to ask all that ens ballast to go toward it

You know this.. but we don't sweat it at this range -

Evolving situation but the signals been in place (actually) for many days using pure numerical telecon spread. +d(PNA) is already underway leading the period in question. Slow rise...combined with the apparent velocity soaking of the local hemisphere may have caused the GFS cluster to rush things (heredity of progressive bias in the product suite?) to the point where it smears the event machinery to where it can't happen in erstwhile model cycles.. However, with improvements in the recent EPS ens mean/with spread noted, now beginning to 'convince' the GEFs (farther below) (...notwithstanding also the impressive operational trends) I feel there's enough to thread this event with confidence for something. It's being placed during a time and space where at least the telecon's have been projecting we're entering a more favorable pattern foot. Speed of the flow is still an issue, tho. Noting the 00z EPS mean and all spread on the western side.. The erstwhile GEFs had been almost entirely absent with this event/time frame ... but rather abruptly on the 12z ( perhaps arguably started on the 6z), we see a coherency with also spread favoring/correction vectoring toward more... There's also a bit more of a conceptual/spatial aspect, where typically a Lakes cutter ( in this case two, interestingly enough...) is often followed by a planetary wave decay-induced -NAO response that drills the successive storm track(s) farther E. So that lends to the general scope of what's going on through this current 2 or 3 weeks synoptic adventure. Noted that there is an off and on signal for 20th/22nd .. this does not cover that period.

Yeah been saying this for years actually. It’s not even just anecdotal, either. If we think about H.A.’s statistical approach, which focused on the precipitation distribution/anomalies as they correlate to index mode vs modality ..etc, her conclusions were always that the primary loading pattern is the PNA … The NAO was less correlated. That at minimum argues that blocking down stream is a dubious driver. … NAO -to me - is a wave decay dumpster down stream of the N/A continent interacting with the termination/eastern end of the Pacific R-wave transmission. In other words it’s indicative … not the conductor

heh... ah, just so's we're clear. I wasn't intending to forecast that? I was just musing - some sardonic overtones. Most of that was just so that I could arrive to the "climate wokism" - I think that's funny. Non-binary climate is great

YES! glad someone else noticed the subsume mechanics going on there. I love that type - I know I mention it often enough but ... it is real and is how/why the top shelf events. There's some subjectivity to that. Like the 18-24" in 7 hour Dec 23 1997 event, which was not forecast like AT ALL... But, we mean the big synoptic history deals. Anyway, it's a long way off but ... the Euro did try to do this yesterday in the range on at least one run, too. It could be we are heading into hemisphere that has some of that tendency in the footprint. However, I see aspect related to too much basal velocity in the flow as neggie factor. interesting

Yeah in an isolated observation that was an interesting deepening rate.. It went from like 980 to 960 to 945 mb in 18 hours. RI at TC range.

I noticed a big switch in the AO projections after the 20th - particularly coming from the EPS over night. But it's in all three ens systems. It was more evident in the numerical indexes (long lead), but last night's coverage began better synoptic/spatial layout presentation with a distant +AO hat on the hemisphere. Awesome that the SSW paid so many dividends, huh. What's interesting is the cold-gutted PNA spanning the continent underneath that +AO ... Heights across all of N/A below 60 N, above normal, despite a +PNAP curved structure. I grow tired of explaining these warm oddities about that distant range between the extended and model 'emergent horizon' - perhaps attribution -related. I don't have any compunctions about saying that. We could see utter absurd warm passages of time at any point between the end of the month thru spring that are just so obviously 'different' and weird - despite how people will cloak that eeriness in this mantra about 'this has happened before.' Okay. We've seen this too many times, regardless of whatever package of longer termed air-land-sea index was doing whatever. Obviously, a global warming thing when it's (-)(+) ENSO and either way, February's host 75 F bursts. 70-fuckum-5 in February 4 times in the last 7 or 8 years ... while that ocean temps world over are always above normal, and summer time heat-related deaths are the number one killer all over the planet. That is by definition warming globe. But you see.... there's sub classes of denial that have evolved out of the original narrative. It's kind of like the novel virus theory and pathology... how the pandemic agent strikes a civilization and then given time ... it mutates into a lesser virulent forms? These lesser pernicious types out there are in this compromised head space ...admitting it is real, but are not allowed to talk about it. It's almost a "wokism" thing, I identify by non-binary climate beliefs. Just musing...

Fast flow is a neg interference.

Meanwhile... zip from the 18z GEFs... that's been trending in the EPS though. Little bit of a conflict there huh

I found this 12z EPS mean a bit of an eye-pop frankly... It's not only abruptly more coherent as a signal, there's spread toward Jersey containing some real bombs compared to where this was the 12 hours prior. Did anyone mention this ? sorry - piece of shit work day

I was in Waltham in 2001. We didn't have the March snow pack at that location - probably owing to the "interior" layout of that year? All I remember is telling Harvey Leonard 5 days before that storm there might be a problem with it being in time because heights over Florida were too high. F'n absolutely nailed it. ...I mean, I certainly wasn't proud of it in that case. We got like 10 or 12" outside my apartment - impressive, but a massive bust compared to the leading week of unrelenting cheer leading PR over Earth's Great Red Spot of a storm. Anyway, I remember a lot of disappointments that year. I think it might have been a gaped bum-hole winter for the coast I'm guessing

Some parts to move around but doable at 10 days ( lol ) ... But the tail end of this Euro run is clearly attempting a subsume phase, which are among the most powerful cyclogen mechanism we can find - other than the extraordinarily rare triple stream phases. 1993 March is whopper example of this latter rarity. The Cleveland Super Bomb in Jan 1978 I think was one too. 1978 Feb back here in the E was a two stream but it was on 'roids because it married a weak Miller A response into a Miller B/capture. Kind of a freak Anyway, that much SPV dislodging is interesting. I think the 17th ( or is it 16th now?) is in play but it was likely destined to low/middling system. The phase change of the +d(PNA) is time dependent. It changes -1 SD to +1 over about 10 day span... That's not exactly a huge restoral forcing suggestion when it's that gradual. It's intuitive to think of that as a series of events rather than the big dawg. .. Just thinkin' out loud. That's all predicated on the assumption that current projections don't change ... eek

I'm behind on this thread but ... it was actually a better run for us than the last because this keeps it pure snow for everyone. That last one was a deeper more powerful solution granted, but it ends going over the IP bombs during max which for snow geese ...heh

The only time I've ever cared about retention is when we are trying to break the 'surviving snow depth' record. by that I mean, 30" of stable pack depth. It's hard to exceed that number - incidentally ... I've come to find over the years ... about 7 or so of them, that when nearing that number we start getting weight settling this, or the errant rainy event there. Even in the best years that's true. There are two years that I have seen 36" ... one was 1996 prior to the January thaw, and then there 42" I had near the end of February 2015. Otherwise 30 seems to be the tough threshold

yeah, it'd be more like which signal is successful - which is probably all that matters for this engagement ... - as opposed to which exists. they both do. i'm just taking them one at a time. this period has a lot of facets to overcome, despite the telecon beacon. the "Miami rule" being one of them. the fact that the SPV is excessively too deep over eastern Canada - possibly owing to a suppressive variant of the -NAO ( or it may be a chicken vs egg deal between the two). western heights are an interesting conundrum. there's a tussle going on between the EPO handling and the lower latitude PNA. typically the former precedes the latter ( natural progression of those mass fields) in lag correlation. but what's happening here is the -EPO is popping off in 2 to 3 day impulses. it's sending a negative height signal down the spine of the Rockies ... meanwhile all that is happening, the PNA is in +d(PNA). those are competing forces - not personally sure how that gets resolved but it's probably at minimum a negative interference - which could also be an entirely false scenario if the models are just not handling the EPO domain very well. gee, when has that ever happened.

the issue with that isn't really an issue - thank goodness ... - because we're still talking about 7 days. but admittedly, it's not a good optic. it's a problem that the 17th has had in all these Euro solutions that are trying to push for that event - interesting consistency there when even its own ensemble mean refuses to emerge a better signal for that time and space. anyway, there isn't enough +SPP situated NW of New England. There is in fact on the 00z probably a modest -SPP there ( "SPP" meaning surface pressure pattern). the 500 mb evolution is structured sufficiently for any fast moving Miller A or Miller A/B hybrid to move E of Boston, but the surface synoptics being what they are is causing the evolution to jump over and favor the left exit/entrance regions of the jet mechanics aloft. the sfc pressure layout aspects et al can change in 7 days, so we'll see there. even a modest amount of PP correction may make the difference between a low cutting just enough to ruin the party, or keeping it east... but, the ens ? heh

That ending frame on that Euro is an overbearing -NAO suppression look. That kind of rock bottom -NAO is actually not what people want - or shouldn't if they know what's what. My guess would be that it is better to have models signal the elephant's ass at D10 than on D4 ...In other words, it's unlikely to verify like that.

that's what we're waiting on.. imho i mean, these euro runs fancy a black holes in the d6-10 range, particularly the latter half of that. as you know. the telecon spread wants a big deal between w va and NS routing - we're talking after the cutters here

NAM has 44 kts at LGA, mid way up the boundary layer at 6z ... 36kts at Logan. Also, LI's are -1 and 0 respectively (lifted index)

Oh, I think it's legit from what I've outlined and still is evidenced et al. I'll probably be starting a thread for that as "early monitoring" - or the like - fairly soon.

It's a good approach for the time frame in question - not intending to condescend but keep it from orbit for now... I've also been discussing the 15th+ period as a time that fits the canonical teleconnector correlation/distribution, for cold eastern storm genesis over the eastern continent. These Lakes cutters in the foreground ... they may or may not be influenced by a steadily increasing -NAO exertion over time, but likely not in time to save the winter enthusiasts from a frustrating tour de fault in that regard. Really very impressed by the immense power suggestive by mere 2.5 day-long cycle between very deep and large winter cyclones through the Lakes. Typically a 975 mb humdinger leads an interval of quiescence - not happening is intriguing. An amazing hemisphere really... You know, it's not impossible that someone between Chi town and Indy would receive upwards of 30" between the two events or more, a significant percentage of their seasonal cryo quota spanning 5 days. But it doesn't end there... the third in the series - at least in so far as the Euro - is apparently responding to the forcing of said telecon projections in then running up/or off the EC with another very deep solution. ...All these solutions ...there, here ...everywhere, are subjective to model attenuation-correction tendencies. But ... sufficed it is to say, when they are all sub 980 and even sub 970 mb, they can shed the 20% and still be charming. Anyway, long of the short - I'd be watching the 16-17th (still). It's really not that far away. We've started threads for early monitoring over less impressive signals. It may just be a matter of time before something significant through the 20th (even) comes over the ens horizon - if the 17th fails.

Maybe there's some conditioning of thinking because one of these wind transport events actually did mix down earlier this season but ... that shouldn't "sway" ( pun intended to annoy - ) anyone anyone's thinking. We still have a lower verification score card when it comes to wind events. You have to look at these situations from scratch/uniquely. The environmental set up this time is different, and the differences that are directly observable are limiting factors. Snow pack in the interior will be melting in gob fulls but not before most likely limiting mixing. This system as synoptically handled in all guidance is moving too fast to overcome that. I'm also wondering if the SSTs from the Bite around the horn are getting cold enough now to impose inversion, which would probably by extension keep this as an elevation thing.