Development of La Niña

[nzucker]

Although many were planning on a weak El Niño this winter, warm anomalies have faded and cold water seems to be growing in the Pacific. What do people think about the development of La Niña by spring and summer?

 

Current SSTs, with major cooling in the ENSO regions:

 

Equatorial wind anomalies support further cooling:

 

The warm subsurface in the spring/summer is being replaced by slightly below average waters:

[Mike.Ventrice]

Although many were planning on a weak El Niño this winter, warm anomalies have faded and cold water seems to be growing in the Pacific. What do people think about the development of La Niña by spring and summer?

 

Current SSTs, with major cooling in the ENSO regions:

developmentlanina.gif

 

Equatorial wind anomalies support further cooling:

uwind1.1.png

 

The warm subsurface in the spring/summer is being replaced by slightly below average waters:

coldersubsurface.gif

 

While it has cooled in the east pacific considerably, there is a major MJO event on the horizon. According to my partial fraction VPM indices, GFS is predicting that 850 hPa zonal winds may approach 4 sigma into MJO phases 6 and 7 (West-to-Central Pacific).

 

 

 

This suggests to me a major westerly wind burst over the Western Pacific that should initiate a strong downwelling oceanic Kelvin wave.  Warm water has been pooling in the West Pacific, priming the ocean for the eastward transport of warm water by the potential oceanic Kelvin wave.

 

 

Anomalous subsurface warm water is present at the date line... watch for this warm water to progress eastward with time during the next couple of weeks, erasing the cold anomalies present in the East Pacific.

[wxmx]

As Mike has pointed out, there's a very strong WWB, currently centered just west of Indonesia, that'll probably reach the dateline in about 10 days. I'd expect dampening of the currently strong MJO wave as it reaches the dateline, same with the WWB, but it would still be discernible thru it's Pacific journey. These westerly anomalies, coupled with an oceanic Kelvin wave will halt the current cooling trend and reverse it some...to what degree, I'd think moderate warming, but I'm still not very confident on that, especially if the westerly anomalies persist for a longer perioid of time. After that, the CFS shows a reinstallation of the easterlies coupled with the upwelling phase of the Kelvin wave, which should restart the cooling trend.

 

Latest weeklies:

 

 

 19DEC2012     22.4-0.6     24.9-0.3     26.4-0.2     28.6 0.2 26DEC2012     22.7-0.6     25.0-0.3     26.4-0.1     28.6 0.2 02JAN2013     23.3-0.4     25.0-0.4     26.3-0.3     28.4 0.1

 

 

Low level winds @850mb (past and forecasted):

[GaWx]

 Being that the 2012 ENSO discussion thread is now out of date, I'm starting this one for 2013. Discuss/forecast to your heart's content!

[nzucker]

I already started a thread Development of La Niña so we can delete this one, I think. There is other ENSO commentary in there. 

[GaWx]

I already started a thread Development of La Niña so we can delete this one, I think. There is other ENSO commentary in there. 

 

 I guess the moderators need to decide. In light of fhe other thread, I'm ok if this is deleted but am not sure it should be. This was meant to be a catch-all for all general 2013 ENSO related topics, both regarding current as well as forecasting into next winter (similar to the 2012 thread). If the other thread will take care of that, this one should go although perhaps the other shoud be renamed "2013 ENSO discussion".

[nzucker]

 I guess the moderators need to decide. In light of fhe other thread, I'm ok if this is deleted but am not sure it should be. This was meant to be a catch-all for all general 2013 ENSO related topics, both regarding current as well as forecasting into next winter (similar to the 2012 thread). If the other thread will take care of that, this one should go although perhaps the other shoud be renamed "2013 ENSO discussion".

 

I did do a subtitle of "Rapid ENSO Changes" to indicate it could be more than just the current La Niña talk. We could merge potentially, doesn't really matter. 

[nzucker]

I am expecting a El Nino to develope this summer. Much better conditions for its development should be present.

 

ENSO regions continue to cool with warmer waters leaving the eastern regions. h

 

Here was the ENSO regions on 1.7:

 

Updated map on 1.11 shows much colder water in Region 1.2 and parts of Region 3:

 

There is a long ways to go, but I think a weak La Niña may be emerging. 

[wxmx]

There´s an MJO wave and an oceanic KW about to cross the ENSO regions, so I expect, in the short term (at least 15-20 days) to average warming.

[wxtrackercody]

CPC puts Nino 3.4 at -0.6C as of Monday. Their models continue to show a weak La Nina for the upcoming hurricane season.

 

I'm not sure we'll be able to get a "real" El Nino anytime soon with a cold PDO. It seems to counteract the development of one.

[nzucker]

The 1.14 SST anomaly map shows renewed cooling in Region 1.2 and Region 3, as well as in the PDO regions such as the Gulf of Alaska and California Coast. Global SSTs seem to be dropping as well:

[CoastalWx]

Torching the Plains 1930s and 40s style.

[OKpowdah]

Torching the Plains 1930s and 40s style.

 

There's talk about the worst dust storm season for OK in decades coming up this spring

[OKpowdah]

Definitely can see the significant cooling over the past few weeks. At the same time, as is already being discussed, the increase in AAM and cycle into a +ENSO atmospheric state for the time being.

 

 

[nzucker]

Incorrect. That is the cooling that already happened, there is renewed warming in regions 1.2 and 3, including 3.4. There is no La Nina dude. The consistant posting about la nina by "zucker" over the years has gotten old. This is a steady state neutral condition and nothing more.

 

I don't see why you are getting nasty. The weeklies came in at -0.6C which is, indeed, La Niña conditions. We know that you favor an El Niño this summer, while I don't. It's rare to see a failed El Niño followed by an El Niño...51-52 was a similar analog and it lead to neutral conditions and then a 3-year La Niña. Anyway, despite the advertised Kelvin Wave, the regions have stayed cool, and the Gulf of Alaska has cooled even more, lowering the PDO:

[Abract]

^You need 5 consecutive trimonthlies to be declared La Nina. One reading of it does not mean it is. We saw last year just beacuse it looks it doesn't mean it is or will be. SOI and sub-surface is firmly neutral

[nzucker]

^You need 5 consecutive trimonthlies to be declared La Nina. One reading of it does not mean it is. We saw last year just beacuse it looks it doesn't mean it is or will be. SOI and sub-surface is firmly neutral

 

I know that...that's why I said "La Niña conditions" Reading comprehension FTL. 

[Isotherm]

We're now in a long term -PDO phase, so Ninos will generally be on the weaker side (on avg). After the PDO flipped negative in the mid/late 1940s, we only had one El Nino event until the 1957-58 season. If history follows a similar path, the 2009-10 el nino might have been the only Nino we'll see for another few years at least. The latest ENSO modelling has region 3.4 SSTA generally within the neutral range, +0.5c to -0.5c for the next several months / through summer 2013. I'm not seeing any alarming signs for the rapid development of La Nina, at least not yet. Recent SOI values have been about as neutral and boring as one can get. No major +SOI bursts indicative of easterly trade increase or colder water movement west at this time.

[nzucker]

3.4 will be warming presently as the Kelvin moves eastward, in otherwords, back up it comes. The reason the El Nino did not develope was because of the wave propulsion setup was dealing with La Nina driven GLAMM leftovers that weren't enough to overcome the atmosphere......really easy. IMO we will see a similiar wave propulsion setup this summer......with less interference, you have yourselves a weak El Nino.

 

Setups like 2009 only about happen once a a decade in a -PDO phase.

 

The warming never really happened, and now we've seen another impressive burst of cooling:

Definitely looks like a solid chance for a Nina. 

[Mike.Ventrice]

The warming never really happened, and now we've seen another impressive burst of cooling:

pacsst1.28.gif

Definitely looks like a solid chance for a Nina. 

 

 

Actually it did, nor has there been much cooling. Notice how the cool/warm pools moved around a bit. Nothing big.

 

Guys, these oceanic Kelvin waves moves at roughly 2 m/s.. so the adjustment will happen over a matter of months! The downwelling oceanic Kelvin wave that myself and others posted about with regards to upcoming warming in the east Pacific is still approximately located at the date line. It will still be a month or two before we see it get all the way to the East Pac and reduce the negative SST anomalies or swap them to positive anomalies.

 

[skierinvermont]

The warming never really happened, and now we've seen another impressive burst of cooling:

 

Definitely looks like a solid chance for a Nina. 

 

Never really happened? Weekly SSTs rose from -.6C to -.2C as wxmx predicted back on Jan 12 for short term warming due to the kelvin wave. 

 

Now they appear to have probably dropped back around -.7C. 

 

However, time is rapidly running out for a Nina to occur. Very warm subsurface anomalies are migrating eastward into region 3.4. Looks like classic development of an El Nino to me. Right now I'd go with weak Nino by late summer. CPC gives less than a 20% chance of development of a Nina in their last update. 

[warrinerjr]

The warming never really happened, and now we've seen another impressive burst of cooling:

pacsst1.28.gif

Definitely looks like a solid chance for a Nina. 

 

Weeklies went from -0.6 to -0.2. The only region that cooled in this past weeks update was Region 1+2 which is known for its volatility.

 

I don't see why you are getting nasty. The weeklies came in at -0.6C which is, indeed, La Niña conditions. We know that you favor an El Niño this summer, while I don't. It's rare to see a failed El Niño followed by an El Niño...51-52 was a similar analog and it lead to neutral conditions and then a 3-year La Niña. Anyway, despite the advertised Kelvin Wave, the regions have stayed cool, and the Gulf of Alaska has cooled even more, lowering the PDO:

sst1.17.gif

 

Its a stretch to call one week below the -0.5 threshold quote " La Nina conditions". We had several weeks back in the fall that were above +0.5 in the weeklies and it sure didnt feel like "El Nino conditions" then either. One week its enough to declare" blank conditions" in my opinion. It would be unprecedented to have a "La Nina - La Nina - Neutral - La Nina - La Nina - La Nina" series. Im going with the stats and saying that 5 out of 6 isnt going to happen. I also wouldnt call this a "failed nino", sure it was failed if you take the models as gospel, but the writing was on the wall WELL before the models finally picked up on it. The weak-moderate event the models were forecasting was never going to happen when we couldnt get a steady line of -10 or stronger SOI's and the GLAAM stayed in the tank all summer... it was a neutral event, and anyone who follows ENSO evolution intimately knew it.

 

This past year's ENSO evolution was certainly effected by the leftovers, atmospherically speaking, of the prior two La Nina's. This coming summer, that wont be as strong of a case and the current subsurface temp anomalies have a more Nino-ish tilt to them than do a developing Nina one. Not saying it cant happen, just saying the signs arent on the wall for a move in the La Nina direction long term. I dont see anything in the extended period that would lead to an immediate "ah ha" with regards to +10 or greater SOI's. Total and Relative AAM remain positive ( high ) and the tendency of the relative AAM has turned back positive as well. Also, ENSO events RARELY strengthen in the Feb. - May time period. Most ENSO events gravitate toward neutral in the spring and early summer months, only to gain strength and momentum to one side or the other in the Jul. - Oct. time period with a peak typically in the Nov. - Jan. time period.

 

Lastly, the PDO isnt based just on what happens in the Gulf of Alaska... its everything above 20N in the Pacific. Things warm and cool and if you look at the total profile above 20N, the PDO is certainly negative, but its not at moderate to strong levels.

[wxmx]

Short term: SSTAs have cooled some after last -0.2 weekly, but this cooling is going to be short lived as I expect steady conditions to slight warming for the next 10 days, especially in the western regions.

 

Medium term: I still expect cooling from mid Feb to mid March on average, but not that much cooling, maybe just enough to keep weeklies around -0.5. Reasoning lies mostly behind the upwelling phase of the MJO

 

Long term: There are mixed signals. Usually in these cases is better to go with neutral, which I favor at the moment (50%) vs El Niño (30%)/La Niña (20%). If cooling is stronger in the mid term or it lasts longer than expected I would probably switch probabilities between the girl and the boy. 

[nzucker]

Never really happened? Weekly SSTs rose from -.6C to -.2C as wxmx predicted back on Jan 12 for short term warming due to the kelvin wave. 

 

Now they appear to have probably dropped back around -.7C. 

 

However, time is rapidly running out for a Nina to occur. Very warm subsurface anomalies are migrating eastward into region 3.4. Looks like classic development of an El Nino to me. Right now I'd go with weak Nino by late summer. CPC gives less than a 20% chance of development of a Nina in their last update. 

Most of the models see a neutral ENSO picture for the next 6 months:

 

The warming was very short-term and never brought us near another El Niño as some people talked about. I know a lot of people were saying that this coming summer would resurrect the failed Niño of Fall 2012 with a slightly stronger +ENSO event, but I'm not seeing weak Niño based on subsurface, SSTs, u-wind forecasts, etc. The subsurface has actually been cooling at 55m and 110m during the month of January, not warming. The only thing preventing a full-blown La Niña is the AAM signal right now, and the recent Kelvin Wave. 

 

I think CPC is being conservative about La Niña (even with writing on the wall) but we'll see...I of course would prefer a weak Niño for next winter but doubt it happens. 

[skierinvermont]

Most of the models see a neutral ENSO picture for the next 6 months:

modelenso.gif

 

The warming was very short-term and never brought us near another El Niño as some people talked about. I know a lot of people were saying that this coming summer would resurrect the failed Niño of Fall 2012 with a slightly stronger +ENSO event, but I'm not seeing weak Niño based on subsurface, SSTs, u-wind forecasts, etc. The subsurface has actually been cooling at 55m and 110m during the month of January, not warming. The only thing preventing a full-blown La Niña is the AAM signal right now, and the recent Kelvin Wave. 

 

I think CPC is being conservative about La Niña (even with writing on the wall) but we'll see...I of course would prefer a weak Niño for next winter but doubt it happens. 

 

 

I don't think anybody expected us to go from -.6C to El Nino in the space of 2 weeks. All I see are predictions of short term warming from the Kelvin wave, which did occur.

 

55 and 105 tell us about the next 3 months, which isn't enough time to reach official Nina status. Also development of a Nina this time of year is unheard of. 155 is very warm and spreading east. 

 

The model mean you posted uses data that is a month or more old.. the development of the west pac warm pool over the last month has continued. It will have to continue to strengthen and spread east to get a Nino by fall, but it should at least inhibit a Nina. 

 

 

How about a friendly bet like (same as from the other thread). 

 

 

I'll even give you 2:1 odds in your favor. If we get an official Nina in the period up to and including JAS*, where a Nina is defined as 5 consecutive trimonthlies below -.5, I give you $40, if not you give me $20. 

 

*JAS = July August September

 

 

AND/OR

 

2:1 odds in my favor on the development of an official Nino before and including NDJ.

 

 

Either bet should be easy if you really think a Nina is (or even might be) coming, or if you are so sure a Nino is not. 

[nzucker]

I'm talking about for next winter...no one would expect a full-blown La Nina in late winter/early spring. That's when ENSO usually dies off..

 

I don't think anybody expected us to go from -.6C to El Nino in the space of 2 weeks. All I see are predictions of short term warming from the Kelvin wave, which did occur.

 

55 and 105 tell us about the next 3 months, which isn't enough time to reach official Nina status. Also development of a Nina this time of year is unheard of. 155 is very warm and spreading east. 

 

The model mean you posted uses data that is a month or more old.. the development of the west pac warm pool over the last month has continued. It will have to continue to strengthen and spread east to get a Nino by fall, but it should at least inhibit a Nina. 

 

 

How about a friendly bet like (same as from the other thread). 

 

 

I'll even give you 2:1 odds in your favor. If we get an official Nina in the period up to and including JAS*, where a Nina is defined as 5 consecutive trimonthlies below -.5, I give you $40, if not you give me $20. 

 

*JAS = July August September

 

 

AND/OR

 

2:1 odds in my favor on the development of an official Nino before and including NDJ.

 

 

Either bet should be easy if you really think a Nina is (or even might be) coming, or if you are so sure a Nino is not. 

[skierinvermont]

I'm talking about for next winter...no one would expect a full-blown La Nina in late winter/early spring. That's when ENSO usually dies off..

 

Oh well then we definitely should not be talking about the shallow and/or eastern subsurface. Those are the waters making surface in the next few months. We should be looking to the deep western waters. I would say that the warm pool there at least dictates a warm push in R3.4 during the summer, but too early to tell if it will be enough for a Nino. 

 

[nzucker]

Oh well then we definitely should not be talking about the shallow and/or eastern subsurface. Those are the waters making surface in the next few months. We should be looking to the deep western waters. I would say that the warm pool there at least dictates a warm push in R3.4 during the summer, but too early to tell if it will be enough for a Nino. 

It looks to me as if the -PDO signature is strengthening and there's also a cold push in the eastern regions from the subsurface. Whether that cold push is reinforced or eroded from the warm pool to the west remains to be seen. 

[JBG]

It looks to me as if the -PDO signature is strengthening and there's also a cold push in the eastern regions from the subsurface. Whether that cold push is reinforced or eroded from the warm pool to the west remains to be seen. 

It seems with the overall -PDO phase that El Niños really have trouble getting going.