Converged on a 12/21/2024 coastal storm, however ... much higher than normal uncertainty relative to very shortterm. May need nowcast for impacting east/SE regions

[Typhoon Tip]

This is intended for a long lead experimental outlook. 

There is a very coherent large scale signal emerging in the deep mid and extended range, roughly 10 to 13 days from now, spanning the Pacific circulation ... and how that transmits forcing across the conus is intriguing.  Using the EPS mean from 00z, we see the changes up stream over the Pacific Basin.  Below is the D6 hemispheric layout, followed by the D11, indicating a rather rapid onset of wholesale mass field deltas - particularly notable, .. the region N-NE of Hawaii. 

 

As the annotation states...it doesn't have to.  There are idiosyncratic ways by which the mass of the atmosphere is conserved; given that all this takes place in 3-dimension spatial differentials and ad nausium popsicle headaches...  the short version is that it's not always always very visible.  but, in the ideal sense, the ridge responds more, and there is a coupled trough response down wind that often hosts index restoration events.    The numerical teleconnectors are showing some new sagging in the EPO, with additional amplitude in the PNA.   These subtle albeit non-zero value nuances I suspect are the beginnings of suggesting an active interlude ..rough with the timing of the solstic give or take.

 

 

[Go Kart Mozart]

At first glance, I thought someone was forecasting the solstice, lol.  Euro AI continues to intrigue me...and it has been showing a stormy-wintry look in this time frame.

 

 

[brooklynwx99]

yeah, the EPS really beefed up the +PNA through AK. could see something popping around this time

[mitchnick]

These guys seem to like the idea too.

https://x.com/bamwxcom/status/1866187927140663665

[H2Otown_WX]

Definitely a signal around the 20th-21st on the GEFS:

[Chrisrotary12]

I much prefer this type of long range… sniffing out and event as opposed to seasonal forecasting. 
 

I can’t be the only one who looked at the above, did the math and thought “there’s the grinch”.

[Typhoon Tip]

mm   didn't really like the direction of the ensemble means overnight... 

what's interesting is that the pacific outlook/changes appeared to still be in tact as far as spatial and spatial-temporal aspects, but the ens means ( worst offender, gefs ) are actually going the wrong direction with the flow down stream across the continent.  the means is attempting less ridge response ..even looking increasing zonal down wind of that deep trough situated n-ne of hawaii.

that's the wrong correlation/direction.  compare this below to the previous 222 hours, and the modulation is going an unexpected direction.  we'll see

[brooklynwx99]

GEFS shifted back to a stronger +PNA

[brooklynwx99]

also the ECMWF shows the full latitude ridge nicely

[Typhoon Tip]

4 minutes ago, brooklynwx99 said:

also the ECMWF shows the full latitude ridge nicely

12z gefs was incrementally improved over the previous two run cycle re the 17th - 24th, wrt the handling of the pac and the subsequent ( implied ) forcing over western n/a  - forcing it has been somehow skipping.   heh.

edit, oh you already posted that -

[Damage In Tolland]

Some signs of cross polar flow in the pole regions later in month 

[Typhoon Tip]

that's quite the big storm there on the euro -

the thing is, it's showing really the incredible potential inherent to that week - i mean, it's getting to that solution with handicaps.  a bigger western ridge and that's a triple stream phaser... very rare indeed.

where is f* is the western ridge!   jesus h

anyway, regardless of the idealized state ... which never happens anyway, this run (operational) did show at least more western ridging and immediately that happens.   long way to to go

[Prismshine Productions]

that's quite the big storm there on the euro -
the thing is, it's showing really the incredible potential inherent to that week - i mean, it's getting to that solution with handicaps.  a bigger western ridge and that's a triple stream phaser... very rare indeed.
where is f* is the western ridge!   jesus h
anyway, regardless of the idealized state ... which never happens anyway, this run (operational) did show at least more western ridging and immediately that happens.   long way to to go

What you think the potential would be if it did triple phase? That was one heck of a storm as is

Sent from my SM-S146VL using Tapatalk

[brooklynwx99]

@Typhoon Tip here's your trend. GEFS has become much more meridional with the ridging out west as the Pacific trough corrects towards the Aleutians

[40/70 Benchmark]

1 hour ago, brooklynwx99 said:

@Typhoon Tip here's your trend. GEFS has become much more meridional with the ridging out west as the Pacific trough corrects towards the Aleutians

That ridge is ideally placed out west.....only thing I don't love is a ridge also INVO 50/50....risks abound as far as track, but I understand the emphasis right now is on just sustaining a coherent storm signal. This storm today is precisely the type event that we usually get around xmas, so maybe somewhat of a different sequencing this year...we hope.

[40/70 Benchmark]

For all of the mocking of the NAO out of deference to the Pacific over the course of the last several years, this sequence is an illustration of the value of the NAO. That EURO OP output looks primed to bury upstate NY to me. Would be nice to lodge that PV a bit closer to Hudson Bay, as opposed to directly centered over Greeland...pretty hostile polar look there. The EPS is a little better.

I realize OP runs are futile right now....just looking.

 

[40/70 Benchmark]

We could also just luck out given the placement of that ridge out west, despite the hostile polar fields....ensembles have that vibe....EPS and GEFS. Interesting to watch. Trough placement may make it tough to hug too much, despite the look up north.

[brooklynwx99]

16 minutes ago, 40/70 Benchmark said:

We could also just luck out given the placement of that ridge out west, despite the hostile polar fields....ensembles have that vibe....EPS and GEFS. Interesting to watch. Trough placement may make it tough to hug too much, despite the look up north.

also, it does look like some TPV involvement modulates the height field downstream... notice the W flow in SE Canada compared to the ripping SW flow we're seeing today

[40/70 Benchmark]

2 minutes ago, brooklynwx99 said:

also, it does look like some TPV involvement modulates the height field downstream... notice the W flow in SE Canada compared to the ripping SW flow we're seeing today

Yea, I saw that...but I'm all set entertaining the notion of (or relying on) PV lobe infusuion for decent snowfall. Again, none of this skepticism is directed at John....no issue with the thread at all and is def. warranted.

[Typhoon Tip]

1 hour ago, 40/70 Benchmark said:

For all of the mocking of the NAO out of deference to the Pacific over the course of the last several years, this sequence is an illustration of the value of the NAO. That EURO OP output looks primed to bury upstate NY to me. Would be nice to lodge that PV a bit closer to Hudson Bay, as opposed to directly centered over Greeland...pretty hostile polar look there. The EPS is a little better.

I realize OP runs are futile right now....just looking.

 

having an anticedent -epo that precedes the onset +d(pna) is a very effective means for laying in a negative temperature anomaly along 40n ... all the way across.  

the -nao, particularly one biased over the western limb, that's not hurting to maintain cold air - it's just not abundantly necessary. i don't speak for everyone but much of the 'hostility' that's emerged over the last decade ( i suspect ) is like 'we were always lied to' resentment.   sort of.  but it was a good thing, because really these winters and their ongoing observation along the life-cycle of so many events ..et al, they have been exposing that aspect.  previous to that, the 1990s popularized the nao as though it were this silver bullet for things to happen and it just was never true. 

in fact, the former circumstance presages/excites cyclogen parametrics between colorado-like to cape cod-ness .. in general, which ride along the baroclinic axis/ thickness gradient.  so long as one's latitude is n of that storm's track ... probably going to do alright.    until 2056 or so, when cold air just simply mean 42 instead of 32 ... lol

 

[brooklynwx99]

i mean, damn. 2 sigma ridge over MT stretching up to the heavens lmao

TPV trying to stretch down into SE Canada, weak WAR. it's honestly not too far off from the Jan 2022 setup. obviously here the antecedent airmass isn't as good, but it's analogous

[40/70 Benchmark]

15 minutes ago, Typhoon Tip said:

having an anticedent -epo that precedes the onset +d(pna) is a very effective means for laying in a negative temperature anomaly along 40n ... all the way across.  

the -nao, particularly one biased over the western limb, that's not hurting to maintain cold air - it's just not abundantly necessary. i don't speak for everyone but much of the 'hostility' that's emerged over the last decade ( i suspect ) is like 'we were always lied to' resentment.   sort of.  but it was a good thing, because really these winters and their ongoing observation along the life-cycle of so many events ..et al, they have been exposing that aspect.  previous to that, the 1990s popularized the nao as though it were this silver bullet for things to happen and it just was never true. 

in fact, the former circumstance presages/excites cyclogen parametrics between colorado-like to cape cod-ness .. in general, which ride along the baroclinic axis/ thickness gradient.  so long as one's latitude is n of that storm's track ... probably going to do alright.    until 2056 or so, when cold air just simply mean 42 instead of 32 ... lol

 

I just refeenced the NAO as a potential track modulator....had nothing to do with cold.

[40/70 Benchmark]

5 minutes ago, brooklynwx99 said:

i mean, damn. 2 sigma ridge over MT stretching up to the heavens lmao

TPV trying to stretch down into SE Canada, weak WAR. it's honestly not too far off from the Jan 2022 setup. obviously here the antecedent airmass isn't as good, but it's analogous

Yea, like I said...that set up a month or two later could work for the coast..

[brooklynwx99]

Just now, 40/70 Benchmark said:

Yea, like I said...that set up a month or two later could work for the coast..

yeah inland is going to be favored here, agreed. coast can be on watch with tempered expectations at this juncture

[40/70 Benchmark]

10 minutes ago, brooklynwx99 said:

yeah inland is going to be favored here, agreed. coast can be on watch with tempered expectations at this juncture

I actually hadn't posted that, but meant to. I would be alot more excited in January or February inside of I 495 and especially rt 128. I am screwed if winds are NE, as opposed to NNE. Get to like ASH and it may be okay.

[brooklynwx99]

notice how the Pacific trough has been trending more equatorward with more AK ridging

[40/70 Benchmark]

I needed some animation to warm the heart and sooth the soul...

[Typhoon Tip]

higher than median confidence about it in my perspective at this point ...this will turn out largely to have been another success in extended/long lead signal determination...

this doesn't do much - yet - for those seeking a dose drip, i know.  ha!  but steadily ... the numbers of individual operational run cycles finally biting on the canonical synoptic construct has been getting more frequent - they are converging on the advertisement.  it lends to said confidence...  it's not like these are throwing out nice patterns and/or embedded events in an antecedent dearth of signal - that's the key

this 12z gfs really can't get any better from this range in term of the 500mb evolution leading up to this chart and then thru the interval and it's spot on.   i don't have a problem anymore with the idea of spending time ferreting out objects in time. it's noted the ggem has a continuity with the +pnap more than less like below.

[Typhoon Tip]

ha ... love the suggestion for repetitious cycling   ...but that's way off

[Roger Smith]

Will go Dec 30-31 for big event, pattern will need to shift for it to be wintry so if it does not shift, event will be a surge of record warm followed by strong winds. Possible inland to GL snowstorm.  If pattern shifts, winter storm for coast also. Big energy peak then anyway. We'll see what it has to work with.