Typhoon Tip

The thing about that 21/22nd system of great eye appeal is that the GFS just served us a ghoster earlier this month - lest we forget. Remember - The Euro never had it... The GFS, insistent spanning two or three consecutive days, pummeled us with a solid mid grade warning level snow storm/nor'easter ... waiting until 72 hours out to finally nod to the Euro taking too far SE to matter - and weaker, too. This looks eerily similar to me. Although the teleconnector footprint seems better this time, go - yeah.. Focus on the Saturday thing first.

This is an impressive Hemisphere ... every cycle I've seen over the last ...5 or 6 back-to-back, has edged more impressive in the general large scale frame-up ... https://www.pivotalweather.com/model.php?m=gefs&p=500h_anom&rh=2021121312&fh=204&r=nh&dpdt=&mc= And, we see on the 22nd there is a mean negative tilt high power trough lifting along NE Coast... Probably don't have to look; foregone conclusion there are several individual members toting along a significant event there.

course... I hadn't seen the 12z Euro ... but it doesn't change the deterministic status ... for now.

I guess it depends what one means by "game" ... Even relative to 5 days out mm...a minoring wintry profiled scenario is on the table to N CT/RI... That's a suppress b-clinic open wave that's putting down icing/mix in the interior from what i'm looking at... probably light snow in southern VT. Lest we forget, cold exertion in the bl/ageo forcing is routinely underestimated, even in higher resolution reputable guidance types - which frankly ..this latter has been rattled in confidence lately anyway.

Focus is on the bigger ticket 'plausibility' out there around the 22nd but the foreground event over the weekened ( centered on 144 or so hours ...) is worth considering ... probably lower significance? sure, but I think that's advisory icing in the interior ending with grits and flurries, with low snow/mix tots in southern VT/NH. The air mass ahead is new post fropa. Altho not excessively cold/dry by any stretch, pressures are rising through NNE - that tends to lead to more ageostrophic/925 mb N llv flow in the interior central/southern NE regions - probably feeding in lower DP. Minor situation overall, but one that looks like a smoking gun for under-estimating hygroscopic cooling. SO, with weaker WAA associated with that flat baroclinic bulge rippling by underneath, it "appears" from this range/blend, to be the right ratio wrt to not overwhelming the llv cold.. Probably some modest frontogenic tendencies over top, too. The thing with the 22nd, ... to me, most GEF individual members carry an event from the TV up the or E of the App spine, and transfer some sort of Miller A/ B hybrid. Obviously the 06z was an impressive 20 mb calving in 12 hours absurdity or whatever Kleenex and magazine that was. It was an outlier... Agree with Will.. the general flow scaffold from 100 W to Greenland provides the 'needle thread' ... it is noted that GGEM dropped the system altogether. The Euro actually had that thing 3 days ago as a historic bomb cutting straight across ...which we rightfully 86 that silliness. But, the 00z run ..as far as I can tell, doesn't even have it. It also looks to have fallen out of sync with it's own ensemble mean. All the while, the hemisphere seems poised to click cogs into a -(wpo;epo) couplet up there, with the NAO probably doing it's thing as a transitive/non-linear large scale wave forcing - in other words... it magnitude and placement is wildly uncertain. Bottom line, vastly too early to be specific about the 22nd.

Yup yup some vestigial compression there … but I’d be willing to hedge the totality wins there. It’d keep things moving along but from orbit that’s cold ptype events verifying STL-PWN while the construct lasts.

Yeah I mean considering margins for error that’s already likely getting it done … we’ve ended up just fine in the past heading into less impressive looks.

Haven’t seen the individual members but that look argues several members likely carry along significant event from the nadir of that trough to NF

That look supports a seasonal arctic/polar hybrid air strike along the NP -NE axis

18z GEFs mean sweetening the deal …

alright - who's high on everyone's shit list now ...

Euro trended N from 00z with that 18/19th system, tho. That said, I suspect it is too amped regardless... It's applying that spontaneous energizing thing it does when D5--> 6 relay, where everything its carrying along thru day 5 gets a boost ... like a participation trophy for being on the charts at all... But there are two different biases in play. One, models et al having to scale back deep mid/ext range systems to saneness as they get closer in time. That's a whole 'nother annoyance. The 2nd one is the Euro has to do that, anyway - ...it's always done that.

GEFs made a significant adjustment approaching D10 ... looks much more 00z EPS like ... Strong -(wpo; epo) regime approaches the Alaska sector. This three wave pattern looks rather stable, too -

mm Still yet another valid convention/destiny with that, tho. The -EPO on top of a -PNA changes the map a little. And, although a little, those nuanced scale differences can mean huge sensible impacts along various climate zones. Like ...( most know this, but - ), but if we flood cold into Canada off the -EPO loading pattern ( and to wit, this one really is outright modeled to actually do that in both major clusters ...), and then the -PNA drills Pacific flow across the continent, S of 40 N, that can lead all kinds of winter storm problems, regardless of the exact phase state of the PNA. Blah blah, but events are more overrunning and sheared along steeper inversion as the storm profiles. Folks tend to look for the idealized set ups. Like the coveted -PNA --> + PNA modal switch that leads to grandpa's Archembault coastal - heh. But -EPO with -PNA can result in positive tilted mean L/Ws that situate road SW flow at mid levels from NM to MN ... with flat waves running along the cold-thickness gradient underneath, each capable of moderate mixed QPF events. If this were no -EPO ..I wouldn't be posting this. But seeing and knowing that looms pretty solidly in both continuity and cross-guidance clustering, I'm inclined to believe that the actual lower tropospheric baroclinic axis ( Dec 20 to Jan 7 or so...) may in fact end up S of the mid level flow.

The dailies of the 00z operational models ...wow, was that a fantastically active pattern out there post Thursday's correction front... I don't buy the model's being successful at loading 45 to 50 N across N/A with sub 534 dam non-hydrostatic heights, and then undulating mass fields along and S of there in order to penetrate 558 dam hydrostatic heights so wildly around mere 18 to 30 hour periodicities... Nope - Fyi - Hydro' vs non-hydrostatic heights are two different atmospheric height metrics: one integrates theta-e into the column, the other doesn't. Since it takes energy to evaporate water into gaseous form ... that is why thickness (hydro') will always be lower than the geopotential heights (non-hydro') - ingesting water into the column takes the gravitational potential energy to do it. Gravitational potential energy is a fancy physics phrase that just means how far your brains splat away from your skull when you fall from that elevation. The more, the higher the starting point...etc... But in this day-and-age of attention span I'm sure I've already lost the reader in that digression. Anyway, I think it is more likely that weaker embedded wave mechanics in stream(s) will modulate the flow synoptics more realistically along shallower N-S variance. That means ... less amplitude. The first most guilty of that above is the Euro - toss that run. That said, there is definitely in my perspective, an early coalescent notion for a Dec 22nd system. As mentioned yesterday ...the entire period nearing the Solstice and then extending ... probably out to the end of the month or even turning the page, appears more baroclinically charged in mean of that period. If the 22nd bears holiday fruit, it may not be the only Xmas cake in the mix.

That's similar to my d(t)/d(T) ... I had 39 rocket to 57 in somewhere between 15 and 20 min. Nashoba Valley, where Ayer resides, does this though. It whips out like everywhere else but because of the geographic nadir, it kind of holds the coldest until it can't and scours out dramatically like that. 61 now

Up to these recent hours, Kevin. ... Maybe not "now" and going forward - course I could have said the winds "were" light ..but heh. Anyway, checking HFD/ORH ...etc not seeing wind advisory scaling right now anyway - that may change..just sayin'.

It's because the wins are light ... The old index finger rule of 22kt at 925 mb from the S in order to scour lower than 2K seemed to work pretty well to seriously f-up a lot of "poor"casts this afternoon for those of us tucked in the murky meat locker E of the Worcester Hills... It seems both this and the last were both over-assessed for wind. interesting -

It seems to me ... for now, it is more of 'period of interest' across the span - and it may last into early Jan, too. Uncertainty is at a surplus right now with discrete systems, while the orbital look is clearly a pattern change toward colder after D5 or 6. I mentioned this awhile ago but mode changes don't lend to model performance. Speedy gradient ripper flows don't, either. Here? We have both those occurring at the same time. The 20th could end up the 23rd, back to 18th, out to the 24th... and then ending up on the 19th, before it really happens on the 22nd, ... before the end of the week in the models. Could even procession through quick hit buck-shot pattern.

heh... you can't trust anything about the discrete features embedded in that flow outside of D5 for a couple of basic philosophical reasons. 1 ) pattern change; for a lot of deeper operational physics reason, mode reshuffling in the atmosphere lends to enhancing model errors/lowering confidence in any daily solution. That D6 to 12 is whopper pattern change. 2 ) gradient rich/velocity soaked ambient flow is compressing waves into the x-corrdinate ...while lengthening to conserve momentum/if losing out to the speed/shear smearing altogether. Don't need pattern change to drive enhancing error in that sort of regime, yet we got that to contend with, too. The aspect that is higher confidence is cold loading and it should be seasonal prior to Xmas ... perhaps even by next weekend.

This 18z GFS looks cold mean by the 19th! Clearly this progressive pattern is causing model performance havoc as they are consummately correcting to the next 'cog' in the flow... This big heat thing is really gone for us. 24 from now we spit a warm sector ... then knock back normal for a couple of days. I wouldn't be surprised if the gig on Thursday is delimited to a day - projecting trend is all... That layout by D9 "looks" like aft of a -EPO loading event ...yet the EPO only looks like it's neutralized. You gotta see the nuances in the flow...and what is going on out there in the EPS and GEFs mean combined, by D9+, is that the PV N of JB is low enough relative to Aleut. neutral EPO domain, to trigger a NW conveyor through the NW Territories of the Canadian shield. That's why we see a pretty good loading into the S eventually SE/Ontario by 8-10. Also, it's meaningless beyond entertainment, but that 18th thru the 21st in the run is probably a phat ice storm.

Some of us said 2 or 3 days ago that these warm domes at this time of year, ...more frequently than not, turn out to be transient warm sectors - that means, in and out ... two days or day and a half. Some times I wonder if the person who makes statements like this, "Not sure why the panic.." are in fact reflecting their own reaction ... haha. Givin you shit. Anyway, it is clear that it will be colder prior to the holidays. "Weather" that includes snow fall, who knows. Kidding aside, it was voiced that this may turn out to be transient. GFS and GGEM are in agreement for an oscillatory pattern through D8.. There is in fact two distinct warm ups. The first centered on 54 hours, give way to shallow N-door boundary settling S... and seasonality for 2 days..Then, the warm sector next Wed-Thur... depends but magnitude right now ( to me ..) looks pedestrian anomaly and not too outrageous. I think those 75 ideas sailed 2 days ago when I saw the fact that the flow's predominantly fast, progressive nature would be hostile to "locking" a pattern that anomalous, that long. The oscillatory nature is in fact more supported by the longer termed footprint hemispheric mode.

My hunch is innovation will control nature - probably with separate order dire consequences - prior any models/tech exactly recreating historical examples. Ex… controlling the weather somehow using “forced orchestrated quantum perturbation” - basically, telling the weather what to do rather than waiting around for chaos The problem with modeling is, it will never “see” modulations that have yet to spontaneously occur. That chaos factor is a hard stop. Modeling will always to some degree be at mercy to emergent properties via fractal chaos that have no roots in the prior states. Somewhere out there in the future there may be a technology that can force quantum states in real time; understanding why fractals occur is no longer necessary. until it sets off a new series of unintended destinies.

Right - December 31, 2022

One wonders if the sounding over Des Moines will be like a straight line down from that 20C ... I'm not sure the sun can input enough energy to realize the adiabat at that latitude. what a freak show - half sarcastic here, but good lord