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Winter-lorn much more confidently given a reason to smile.


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I think it must have been a month since I had seen so much as a favorable prognostic whisper.   ...Didn't do much for us back then, if perhaps for being too early in the season, or a season destined not to be, or both - who knows? 

 

Though it's too early for "optimism" - per se - there is now, again, a distant emerging beacon.  The thing is ... this is the sort of emerging signal that needs more time for confidence, because it would buck a hardened persistence by a goodly heft in change.  Seriously.. There are a couple of very interesting tool suggestions in play ...rather abruptly over the last couple of days (if perhaps hinted yesterday I held back due to the apparent absurdity to even suggest it given this stench of Stockholm Syndrome, debacle of an erstwhile sans winter pattern that's been so unyielding...eh hem).

 

A few contributors have been discussing the first week of January ... counter pointed with sardonics and sarcasm at other times, no doubt.  But ... well, I'll just get right into it.  The good-old Canadian, 10-Day temperature anomalies product!  It's a great tool for sniffing out plausible temperature anomaly trends, because ... particularly in the winter, we should be peering NW across Canada.

 

post-904-0-22109000-1450629185_thumb.jpg

 

These units are 1 = .4 SD on this product (from what I have been informed of in the past); which means that up there amid that blue circumvallate in the NW Territories and adjacent, the mean approaches one proper standard deviation on the cold side.  

 

That, in itself, only gets more interesting when noting that the operational trends of the GFS and Euro show gathering mass of cold air above the 70th parallel.  The Euro in fact has 850 mb temperatures between  -30 and nearly  -40 C between western Greenland and the Beaufort Sea/western Canadian Maritimes.  

 

post-904-0-73818000-1450630676_thumb.jpg

 

I would think that between the two most dependable operational model types building cold mass in those regions, combined with a proven, reasonably dependable "anomaly tendency" tool (the 10-Day mean above), this tells me that our quatra-polar-index region is being loaded with cold - and is doing so like not yet seen thus far this early winter season.  

 

If nothing else ... there is plenty of cold air around, and the implication of these disparate sources sort of converging on the same idea is that said cold grows in mass and areal coverage.

 

The question is (beyond whether that actually takes place -- but for just that aspect of this discussion, I believe it will), is where does this cold go from there??  Well ...heh heh... if you believe the overnight GEFs -derived teleconnectors (which I am not sure I fully do given to the earliness/newness of this signal, but we'll see), man we are really close a full on relay event that would severely reverse the character of both sensible, but observable weather at middle latitudes across the NA.

 

Both agencies are now entertaining a three consecutive nightly trend-growth for rising PNA!   

 

post-904-0-91542900-1450631093_thumb.jpg

 

What is missing ?  hmm... I'd like to see the EPO involved.. The index is progged to tack in at about +1 or so SD, right out to the end of week two.   However, ...these things have to be individually qualified (so to speak).  If the PNA flow construct were to succeed, and take on a steep enough meridional vector(s), segments of this building body of cold air could/would come south even to the 40th parallel and beyond.  

This is all conceptual forecasting (nothing discrete) at this time. But, in so far as not having ANYthing to look forward to as winter weather enthusiasts, indicators took a couple/few initial steps toward valid town for reasons to have hope.  

 

One thing I would add, despite the plight, things can turn around with extreme rapidity.  If there are -20 to -40 C plumes of available atmospheric mass, ...forced south by the first week of January.  Believe me, things can turn around in a hurry. 

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The question is whether or not it gets delayed, and if so, for how long?.....but make no mistake about it, it will flip.

 

This is the first time it has entered into the weightiness of the entire ensemble mean of the GEFs vision, by actually showing up in the product(s)

- fwiw. 

 

Anything prior to this was more/mere guess work imho.  The PNA is a very large domain space.  Intrinsically, a single SD is thus sending a larger mass field through a modal change - compared to the smaller NAO EPO domains. That's why, in part, these lesser mass fields tend to stochastic behavior ... changing signs over comparatively shorter time-spans.  It's just harder to change a giant that quickly, wrt the PNA.  So much so that a single SD can send a more significant implication down stream into the NA relay ... Moving it 4 or 5 toward positive, while the run up time is loading/modeled serious cold into the said regions ... are altogether intriguing for me.

 

Additionally, when the PNA is moving en masse in every member ...uuuuusually means there's something significant in the physics of the system instructing that to take place.  What that is, who knows...but again, it takes a strong force to get the giant to roll-over.  

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All of the ensmebles guidance (GEFS, EC, and GGEM) look fairly similar for early January...a more seasonable pattern. You can see how on the GEFS (which again is similar to the others), the Aleutian low has retro'd into a more favorable position.

 

f312.gif

 

 

 

 

This is not a really cold pattern since we'd like to see the EPO ridge poke further north to get a true cross-polar feed, but this is definitely more seasonable. Probably near average and could provide for a wintry chance or two. The NAO is still positive which is hurting...if it was negative with this setup, then we'd probably be colder than average.

 

But a +PNA pattern with closer to average airmass will give some potential. For those who may end up melting down if this pattern averages normal or slightly above and also happen to not see snow out of it....repeat after me: "This isn't a cold pattern", "This isn't a cold pattern". But it is one that is certainly serviceable and with the +PNA spike and seasonable air, there should be chances. Who knows if they end up as cutters or quick snow to rain scenarios instead of a good storm...that's not the point of this post. We can't forecast that type of detail at this lead time.

 

FWIW, this pattern has been getting closer on the ensembles...first at D15-16 a few days ago, it is now down to about D12. Whether it is transient in nature or not, who knows...but it is likely to at least cool us down somewhat whenever it arrives. My guess is it will be transient because I'd be surprised if we flipped the pattern this early in January. But it is the first sign of the retrogression that should take place over the next 4-6 weeks.

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Yep, agree. It's probably not a cold, snowpack pattern...but one that offers up storm chances which is all you can ask. You can see lots of s/w's in the flow which is usually a good sign. Details to be determined.

 

On a more long range scale, we are finally seeing the anomalous IO forcing trying to shut down. It's probably part of the reason we can finally get a more Nino-like +PNA to develop. Forcing should move to near the dateline into early to mid January it seems.

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All of the ensmebles guidance (GEFS, EC, and GGEM) look fairly similar for early January...a more seasonable pattern. You can see how on the GEFS (which again is similar to the others), the Aleutian low has retro'd into a more favorable position.

 

f312.gif

 

 

 

 

This is not a really cold pattern since we'd like to see the EPO ridge poke further north to get a true cross-polar feed, but this is definitely more seasonable. Probably near average and could provide for a wintry chance or two. The NAO is still positive which is hurting...if it was negative with this setup, then we'd probably be colder than average.

 

But a +PNA pattern with closer to average airmass will give some potential. For those who may end up melting down if this pattern averages normal or slightly above and also happen to not see snow out of it....repeat after me: "This isn't a cold pattern", "This isn't a cold pattern". But it is one that is certainly serviceable and with the +PNA spike and seasonable air, there should be chances. Who knows if they end up as cutters or quick snow to rain scenarios instead of a good storm...that's not the point of this post. We can't forecast that type of detail at this lead time.

 

FWIW, this pattern has been getting closer on the ensembles...first at D15-16 a few days ago, it is now down to about D12. Whether it is transient in nature or not, who knows...but it is likely to at least cool us down somewhat whenever it arrives. My guess is it will be transient because I'd be surprised if we flipped the pattern this early in January. But it is the first sign of the retrogression that should take place over the next 4-6 weeks.

Absolutely agree......anything more robust in rogue runs will likely get pushed back.

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Agreed Will, Scoot, Ray ... 

 

Perhaps the take away was, "...This is all conceptual forecasting (nothing discrete) at this time. But, in so far as not having ANYthing to look forward to as winter weather enthusiasts, indicators took a couple/few initial steps toward valid town for reasons to have hope..."

 

Having said that .. things still look okay for either a return to seasonality ( if only transiently so, notwithstanding..) during the first week of January.  But, I do add that the turn around (sensibly) could be rather dramatic - that's sort of a different discussion re acclimation and so forth, just sayin'.  

 

However, I do think the longer term land/sea/air teleconnector sets really favor a sustained pattern change, tho, and it has to do with the simple premise that we really have not seen the more typically correlated warm ENSO, +PNA.. in fact, quite the opposite. We are in fact in a flow construction that is anomalous relative to the those arguments.  

 

The thing with anomalies ... by definition they are transient in time - they have to be, because if they become fixed characteristics of a system in question, what's anomalous?   So, replacing a transient, four-week -PNA odd-ball purposely designed to ruin Christmas by an a-holey god pattern, with a transients ...some other god-awful reason to loathe this discipline too, only leads to one conclusion: the pattern et al is just unstable and hasn't really found a "base-line" state.

 

J/k...  In all seriousness, I would think that a +PNA should emerge here.  I agree that the scale of any anomaly distributions that result cannot be realistically ascertained ...for now.  I also mentioned that I'd like to see the EPO better aligned for the 'coldness' of all.  But you are flat right about one thing .. and, once into January even being + 1 or + 2 in the temperature mean is no killer for chances to recoup wintry events at our latitude.  Keeping the expectation storm down to a dull roar, that's another challenge altogether. .   

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Agreed Will, Scoot, Ray ... 

 

Perhaps the take away was, "...This is all conceptual forecasting (nothing discrete) at this time. But, in so far as not having ANYthing to look forward to as winter weather enthusiasts, indicators took a couple/few initial steps toward valid town for reasons to have hope..."

 

Having said that .. things still look okay for either a return to seasonality ( if only transiently so, notwithstanding..) during the first week of January.  But, I do add that the turn around (sensibly) could be rather dramatic - that's sort of a different discussion re acclimation and so forth, just sayin'.  

 

However, I do think the longer term land/sea/air teleconnector sets really favor a sustained pattern change, tho, and it has to do with the simple premise that we really have not seen the more typically correlated warm ENSO, +PNA.. in fact, quite the opposite. We are in fact in a flow construction that is anomalous relative to the those arguments.  

 

The thing with anomalies ... by definition they are transient in time - they have to be, because if they become fixed characteristics of a system in question, what's anomalous?   So, replacing a transient, four-week -PNA odd-ball purposely designed to ruin Christmas by an a-holey god pattern, with a transients ...some other god-awful reason to loathe this discipline too, only leads to one conclusion: the pattern et al is just unstable and hasn't really found a "base-line" state.

 

J/k...  In all seriousness, I would think that a +PNA should emerge here.  I agree that the scale of any anomaly distributions that result cannot be realistically ascertained ...for now.  I also mentioned that I'd like to see the EPO better aligned for the 'coldness' of all.  But you are flat right about one thing .. and, once into January even being + 1 or + 2 in the temperature mean is no killer for chances to recoup wintry events.   

 

Agreed...I should probably clarify what I mean about "transient"...I was merely talking about the spike in the EPO to mildly negative territory...I do agree the PNA should be positive given the ENSO state and magnitude. I wouldn't be surprised to see it stay mostly positive after the flip coming up here. But I am not quite convinced the ugly Bering/AK vortex is locked out for the next 6-8 weeks after this upcoming change for the better...I could see it trying to come back at intervals in January as the seasonal progression of El Nino tries to fight the waning IO forcing which has helped enhance this December torch from already fairly mild expectations. As Scott mentioned above, it finally looks like the IO is weakening and we may try to start consolidating more tropical convection near the dateline...we'll see if that happens faster or is a bit fussy for a few weeks. My guess was that it might be fussy and we see some oscillating in the EPO vortex which still makes us prone to some bouts of warmth in the first half of January.

 

Hopefully that ends up being wrong and we can keep a mostly neutral (to negative) EPO.

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Yeah I am not sold on Kevin's one eyed pig just gone for the year either. Maybe it tries to come back and wink at SNE again..lol. But, for now...some change is in the offering...and it would sort of go along with euro seasonal. We shall see.

If that pig does come back, it maybe time to waive the white flag, but I don't expect that.

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Winter 2015-'16, much like its predecessor, will begin tame, and then about face and violently change character. Indeed, the earlier benign affect of a season once seemingly destined for a gentle transition to spring, will begin to display it's true bipolar tendencies around the third week of January, or thereabouts, and should be evident by the time that the month draws to a close. It is anticipated that the AO/NAO will average at least somewhat negative as a mean aggregate for the period of December through March. Aggressively biased positive early in, with perhaps one notable period in December when we may encounter one significant, but rogue winter storm; however the greatest impact would likely be to the west of our region for any such storm, and perhaps significantly so. Eastern Mass will be relatively void of adverse winter weather through the new year. The EPO will also likely average positive early on, owed to the potent GOA vortex slinging air masses of Pacific origin throughout the country. It is the positioning of this vortex that is of absolute greatest importance in seasons of this ilk. As illustrated in the chain of graphics below, it expected that this feature will retrograde over the course of the season, as el nino climatology dictates that they are likely to do. This is illustrated quite splendidly and adeptly in the schematics of how I anticipate the season to progress, posted below:

 

November had looked to feature a fairly benign pattern when I had initially examined it a month ago, and that has verified over the course of the first third of the month, to say the least. Atlantic and arctic regimes remain hostile for winter weather. VERY IMPORTANT Aleutian low developing near Aleutian Islands

 

By next month, December,  it is anticipated that the Gulf of Alaska (GOA) Low will set up shop WEST of the area outlined in the November schematic above, although still perhaps a bit to close to AK. The Atlantic also remains hostile, so we are still mild, but the seeds of change are planted for another rough back half of winter Depicted to the left is the door swinging shut on season one.NAO still staves off much of the cold.

 

(January) Depicted to the left is the door swinging shut on season one. GOA Low already in good spot and only getting better. Retrograding and intensifying. NAO still staves off much of the cold.

 

 

Nothing is worthy of melting....I can't post the associated images here, but everything is on track.

 

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Those higher heights in NW Canada look good, Will...still a mess on the ATL side with a weak vortex over Baffin Island.

 

 

Yeah not bad...there will be a cold shot or two if a setup like this verifies...though the real arctic stuff stays fairly bottled up. There's at least a little more disturbance in the NAO vortex showing up here...hopefully maybe planting the seeds for something better further out in January.

 

f300.gif

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Yeah not bad...there will be a cold shot or two if a setup like this verifies...though the real arctic stuff stays fairly bottled up. There's at least a little more disturbance in the NAO vortex showing up here...hopefully maybe planting the seeds for something better further out in January.

f300.gif

Yeah, those low heights on the Asian/Siberian side will probably hold the arctic air on the other side of the hemisphere. Looks like the PV might migrate from Greenland over to the Kamchatka area. However, the strong +PNA should help storms stay south of us, and usher in some modified cold shots with the Plains finally chilling.

I hope that strong Scandinavia/Kara ridge can force the NAO negative. That might dampen heights over the Atlantic and give Europe colder weather as well as increase chances for a Nor'easter.

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Yeah, those low heights on the Asian/Siberian side will probably hold the arctic air on the other side of the hemisphere. Looks like the PV might migrate from Greenland over to the Kamchatka area. However, the strong +PNA should help storms stay south of us, and usher in some modified cold shots with the Plains finally chilling.

I hope that strong Scandinavia/Kara ridge can force the NAO negative. That might dampen heights over the Atlantic and give Europe colder weather as well as increase chances for a Nor'easter.

 

Big Scandinavian ridges are often a precursor to a -NAO further down the line a week or two later...so perhaps this is the first signs of some NAO help, but we're obviously talking pretty far out now (at least into mid-Jan and beyond). And of course, "often" doesn't mean we always get the -NAO to happen.

 

Either way, it is at least promising to see the hemispheric pattern get shuffled on the ensembles. We'll have to be patient...we always knew we would though in a potent El Nino. Hopefully we get a threat in that +PNA pattern in the meantime closer to the New Years and just after.

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Big Scandinavian ridges are often a precursor to a -NAO further down the line a week or two later...so perhaps this is the first signs of some NAO help, but we're obviously talking pretty far out now (at least into mid-Jan and beyond). And of course, "often" doesn't mean we always get the -NAO to happen.

 

Either way, it is at least promising to see the hemispheric pattern get shuffled on the ensembles. We'll have to be patient...we always knew we would though in a potent El Nino. Hopefully we get a threat in that +PNA pattern in the meantime closer to the New Years and just after.

Do you have instances in which it has failed?

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Do you have instances in which it has failed?

 

We had a good one in late January 2012 and it never really materialized into a decent blocking episode. That Scandinavian block and the big EPO/WPO ridge progged for early February was one reason there was still some optimism for a wintry period in early to mid February 2012...but we never did get any NAO blocking and the EPO/WPO ridge really was more in the WPO region and folded back SW in the EPO region and we didn't get a very favorable pattern.

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We had a good one in late January 2012 and it never really materialized into a decent blocking episode. That Scandinavian block and the big EPO/WPO ridge progged for early February was one reason there was still some optimism for a wintry period in early to mid February 2012...but we never did get any NAO blocking and the EPO/WPO ridge really was more in the WPO region and folded back SW in the EPO region and we didn't get a very favorable pattern.

That year was ENSO neutral, right?

Any other seasons that you know of?

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