Weak La Nina Winter

[AfewUniversesBelowNormal]

Nice warming now. Fall pattern is setting up like there won't be a big cold push, maybe for the whole rest of event. Weak La Nina Winter  

[raindancewx]

Given that ERSST V.5 is colder than V.4 in some months (i.e. the 2015-16 El Nino was upgraded to +2.5/2.6 from +2.2), not sure this will ever be classified as a La Nina event, which is why I was going with cold Neutral initially.

It doesn't seem like ASO will be cold enough on the new standard, it's probably -0.3 or -0.4. V.5 has August at 0, September -0.5, so you'd need Oct at -1 - which doesn't seem likely. Oct is probably -0.4 to -0.8.

If it ends up a La Nina on V.4, we may not even know - CPC tends to stop updating the old ONI standardized values a couple trimesters after the new version is posted.

 

[AfewUniversesBelowNormal]

Events peak November-January and 90% of the time the trend continues. 

[AfewUniversesBelowNormal]

The warming isn't strange, SSTs got ahead of the subsurface. 

 

[raindancewx]

Part of me thinks the subsurface cold pool is just going to keep bleeding up for a while to the East of Nino 3.4, mostly in Nino 1.2. If that happens it may be a Peru La Nina more than a "NOAA La Nina", Tropical Tidbits has the anomalies back to -0.3C now in Nino 3.4. Weeklies were back to -0.2C. The 2016-17 La Nina was already three months old by this time, so I keep wondering when we catch up at least? It's not like the green represents much warmer from a super La Nina - its pretty notable warming from a weak, short lived La Nina. A La Nina that is -0.6C in DJF in 3.4 with -1.0 in Nino 1.2 is very different from last year, when it was more like -0.7C / +0.7 respectively in NDJ.

[AfewUniversesBelowNormal]

The subsurface signature is Moderate La Nina. This event will get much stronger on the surface in time because subsurface leads. (this is Nino 3.4 signature)

[sebastiaan1973]

http://www.researchgate.net/profile/Baoqiang_Xiang/publication/271737956_Impacts_of_two_types_of_La_Nina_on_the_NAO_during_boreal_winter/links/5666facc08aea62726ee36e6.pdf this might be interesting for you guys.

Abstract The present work identifies two types of La

Nin˜a based on the spatial distribution of sea surface temperature

(SST) anomaly. In contrast to the eastern Pacific

(EP) La Nin˜a event, a new type of La Nin˜a (central Pacific,

or CP La Nin˜a) is featured by the SST cooling center over

the CP. These two types of La Nin˜a exhibit a fundamental

difference in SST anomaly evolution: the EP La Nin˜a

shows a westward propagation feature while the CP La

Nin˜a exhibits a standing feature over the CP. The two types

of La Nin˜a can give rise to a significantly different teleconnection

around the globe. As a response to the EP La

Nin˜a, the North Atlantic (NA)–Western European (WE)

region experiences the atmospheric anomaly resembling a

negative North Atlantic Oscillation (NAO) pattern

accompanied by a weakening Atlantic jet. It leads to a

cooler and drier than normal winter over Western Europe.

However, the CP La Nin˜a has a roughly opposing impact

on the NA–WE climate. A positive NAO-like climate

anomaly is observed with a strengthening Atlantic jet, and

there appears a warmer and wetter than normal winter over

Western Europe. Modeling experiments indicate that the

above contrasting atmospheric anomalies are mainly

attributed to the different SST cooling patterns for the two

types of La Nin˜ a. Mixing up their signals would lead to

difficulty in seasonal prediction of regional climate. Since

the La Nin˜a-related SST anomaly is clearly observed during

the developing autumn, the associated winter climate

anomalies over Western Europe could be predicted a season

in advance

[AfewUniversesBelowNormal]

2 hours ago, Angrysummons said:

The subsurface has already led. The surface, however is hostile. A moderate la nina looks unlikely.

A gap exists. Subsurface is also leading in the difference pattern wise, look at Atlantic hurricane season. October is setting up La Nina-like in the Northern Hemisphere. 
I did research a while back that shows subsurface is more correlated to things than surface, and the difference was great (although subsurface-surface are usually very correlated). 

[raindancewx]

These are the monthly values that feed into ONI - by ERSST V.5, we're looking at -0.1C for JAS. Maybe a touch colder on the old ERSST V.4 - but its not more than 0.2 or 0.3.

https://www.esrl.noaa.gov/psd/data/correlation/nina34.anom.data

 2016   2.56   2.27   1.67   1.01   0.42   0.10  -0.36  -0.56  -0.58  -0.69  -0.68  -0.47
 2017  -0.44  -0.09   0.07   0.31   0.48   0.46   0.35  -0.15  -0.43 -99.99 -99.99 -99.99

JAS 2016: -0.5C

JAS 2017: -0.077C (-0.1C)

ASO will be stuck in cold-Neutral territory too, barring a drop to -0.9C or more.

[AfewUniversesBelowNormal]

Step outside, it's La Nina

ONI will verify it in time.

Edit: It's kind of silly that we use surface SSTs. sea surface temperatures are more responsive to what is happening than visa-versa. Tropical Pacific is kind of hard to determine but it's classic chicken-egg and I think there is a lot of assumption here about the leader. We are also following the warmest year on record globally and warmest September. 

[raindancewx]

For where I live, the surface SSTs matter for precipitation - the wind patterns, high/low patterns respond more to subsurface, but we're almost never super dry here if enough moisture from a warmer surface skin. Would point out that this last year has been wetter than normal for much of the SW, a region very sensitive to La Nina effects, with mostly La Nina conditions, and the PDO has never really crashed negative. So its not exactly a textbook La Nina, although it has been warm here.

To me the La Ninas / El Ninos with opposite phase PDO states are almost always Modokis and almost always "neutral" like in how the weather is in the West. I'm in New Mexico, and we're looking at 1-3 inches of rain for the next three days, which is more common in Neutrals or El Ninos than La Ninas in October. The city had 9.91" from Oct 1 2016 to Sept 30 2017, way above average (8.67" from 1931-32 to 2016-17). 

I'm not really arguing that this won't "act" like a La Nina at times - my winter forecast will have the SE pretty warm again - just saying there is a real chance it doesn't ever show up as an official event. I'll probably classify it as a La Nina in my records because the other measures are showing it now - the traditional SOI was over +8 for the last month for instance. In my research the lag time between subsurface reaching the surface varies somewhat by ENSO event - so there is a part of me that thinks we have a very strong La Nina next winter, with the very cold waters just starting to really surface in Nino 3.4 in Feb-Apr. Would be similar to how 2014-15 winter was very weak as an El Nino despite lots of warm waters below the surface..but they eventually surfaced in 2015. Your call in August kind of reminded me of this - when the models had a big El Nino based on huge subsurface warming in August 2014.

 

 

[Daniel Boone]

A little confused on whether you're going with a weak or moderate nina Chuck as the one post you say weak but, the latter one's seem to suggest moderate.?. maybe I misread or missed something. Clarify for us there buddy. Thanks.

[AfewUniversesBelowNormal]

Moderate Nina effects... Now and continue... ONI will probably peak Weak Nina ~-0.7

[raindancewx]

I'm starting to think Chuck AND my original claim (cold Neutral) will be right:

ERSST V.5: -0.1C for JAS

ERSST V.4: -0.5C for JAS

V.4 is being phased out - so the question is...will they count this as a La Nina if it makes it on the warmer V.4 but not on the colder V.5? 

http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v4.shtml

http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php

[AfewUniversesBelowNormal]

The -SST burst was pre-event, or predictor. The next wave in 2-3 weeks should be more saturated and longer term. 

[raindancewx]

Here is what the Canadian as of 9.30.17 has - still something of a Modoki with the Central Pacific cooler than the East Pacific and West Pacific. But much more traditional than last year. I'd call it East Central.

Below is what the Canadian had on 9.30.16 for the 2016-17 winter.

 

[raindancewx]

 Weekly        Nino 1.2      Nino 3      Nino 3.4     Nino 4 
 06SEP2017     20.4-0.1     24.3-0.6     26.2-0.6     28.7 0.1
 13SEP2017     19.7-0.7     24.0-0.9     26.1-0.6     28.7 0.0
 20SEP2017     19.3-1.1     23.9-1.0     26.3-0.4     28.7 0.0
 27SEP2017     19.5-1.0     24.4-0.5     26.5-0.2     28.4-0.2
 04OCT2017     19.3-1.4     24.7-0.2     26.7 0.0     28.7 0.1

[AfewUniversesBelowNormal]

Nice cold pool developing now. 

 

[Treckasec]

On 10/7/2017 at 8:36 PM, raindancewx said:

Here is what the Canadian as of 9.30.17 has - still something of a Modoki with the Central Pacific cooler than the East Pacific and West Pacific. But much more traditional than last year. I'd call it East Central.

 

 

 

Hmm... This looks more west than east or central based I'd say! Anomalies are only a teensy bit below normal in the eastern ENSO region, with the deepest blues out towards the west ENSO region in that forecast.

 

 

These are the current anomalies... The anomalies are right up against the coast there, with some slightly above average SSTAs out west. The CFS forecasting the anomaly positions to change does make me curious to see how things may (or may not) change in the next month or two.   

[raindancewx]

4 minutes ago, Treckasec said:

 

Hmm... This looks more west than east or central based I'd say! Anomalies are only a teensy bit below normal in the eastern ENSO region, with the deepest blues out towards the west ENSO region in that forecast.

 

 

These are the current anomalies... The anomalies are right up against the coast there, with some slightly above average SSTAs out west. The CFS forecasting the anomaly positions to change does make me curious to see how things may (or may not) change in the next month or two.   

I meant its more 'east-central' than last year's forecast - i.e. you have actual colder than normal waters by South America instead of a warm Nino 1.2.

[Treckasec]

5 minutes ago, raindancewx said:

I meant its more 'east-central' than last year's forecast - i.e. you have actual colder than normal waters by South America instead of a warm Nino 1.2.

There're only a teensy bit of cool anomalies though. The cooler waters are also cooler than last years forecast in that same area, and the anomalies stretch out for a wider region. The waters out west in the current CFS forecast are also a fair bit colder relative to the waters to the east. I believe this would result in a La Nina being west based as opposed to east-central based.

[raindancewx]

Yeah I get it. Like I said - the important part for the Canadian outlook is it is more of a basin wide event, even though it is still the Central Pacific that is coldest. This is what last year looked like - no cold at all in Nino 1.2 - it was quite warm there. When Nino 1.2 is warm the East fries.

There was no easterly component to the cold at all for winter 2016-17, so relative to last year it is stronger to the east, even though you are right, it isn't really east-central in the Canadian outlook. The Canadian (correctly) had Nino 1.2 pretty warm last year for how cool the other areas were, that's the point, it doesn't this year.

[mitchnick]

On 10/4/2017 at 7:36 AM, raindancewx said:

I'm starting to think Chuck AND my original claim (cold Neutral) will be right:

ERSST V.5: -0.1C for JAS

ERSST V.4: -0.5C for JAS

V.4 is being phased out - so the question is...will they count this as a La Nina if it makes it on the warmer V.4 but not on the colder V.5? 

http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v4.shtml

http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php

Looking at the v5 chart, the closest Enso match to this year (strong Nino 2 years before and Nina preceding year) is 84/85. Now we just have to get cold, but it sure seems reluctant.

[raindancewx]

You have to squint to see it since the oceans are warmer now than before, but if you take out 0.2C or whatever everywhere, 1932-33 still looks like a decent match to 2017-18, at least what the models are showing. I'm definitely using it as a low weighted analog for the winter, the hurricane season remains uncannily close with not just Harvey, Irma, Maria, and Nate, but an active volcano erupting in 1932 - which we may have with Agung.

The Pacific isn't great in the PDO zones for 1932-33, but the whole "warm" anomalies north of "cool/normal" anomalies in the Atlantic that the Canadian has absolutely shows up in 1932-33.

[griteater]

9 hours ago, raindancewx said:

Y

 

Here's an alternate view of the 1932-1933 winter SSTs against the 1901-1930 averages (i.e. 1933 minus 1901-1930) via HADISST

[raindancewx]

Since I can't sleep and the JAMSTEC has updated. It's actually very close to what I have - colder and drier in the West, colder and wetter in the Midwest, somewhat cooler in the coastal SE, but still warm/dry overall. NW/West - interior especially - cold. This was my forecast for anyone curious - https://t.co/ZnvyQletct

The JAMSTEC, like the Canadian, correctly had Nino 1.2 warm last year. Does not this year. PDO also looks less positive, which is probably correct. The "warm" anomalies north of "cool" anomalies in the Atlantic that the Canadian had also shows up in the latest JAMSTEC. The JAMSTEC run has a -0.2 to -0.3 Modoki value for DJF.

The JAMSTEC also has a cold winter forecast for much of the country - including showing the interior West coldest, which is what I put out in my outlook yesterday. It has NM, where I live, only slightly above average, which is pretty close to what I expect. It correctly had a very warm winter for my area last winter.

 

[WidreMann]

3.4 temps have dropped 0.4 C in the past week, and the cooling trend looks likely to continue. We still have a very sizeable subsurface cold pool, with almost no warm anomalies west of the dateline. I'd be surprised if it doesn't result in a cool down of 1+2 (which has also cooled a good bit in the last week or so) and then the basin. Not sure why we're having such a tough time making this La Nina happen.

[AfewUniversesBelowNormal]

This is impressive. Even more so that the surface hasn't caught up yet. 

 

 

[dmillz25]

11 minutes ago, StormchaserChuck said:

This is impressive. Even more so that the surface hasn't caught up yet. 

 

 

With mjo getting stronger the surface won't probably respond for a while 

[Stebo]

2 minutes ago, dmillz25 said:

With mjo getting stronger the surface won't probably respond for a while 

Looking at this below, I would disagree