Weak-Moderate El Nino 2018-2019

[raindancewx]

It looks to me like the subsurface has warmed up some since September in the 100-180W zone. We'll see what the numbers show in early November. October has a very strong correlation to the following DJF in Nino 3.4. Departures are against the 1951-2010 mean of 26.5C in Nino 3.4.

Here are the last five years (2017, 2016, 2015, 2014, 2013) on the subsurface in October, and then what was predicted for DJF using the formula v. reality.

Year          Oct Subsurface         Forecast DJF (v. 1951-2010)     Actual DJF (v. 1951-2010)

2017             -0.97                            -0.71                                    -0.79

2016             -0.92                            -0.67                                    -0.21

2015             +1.91                          +1.75                                   +2.62

2014             +0.53                          +0.57                                    +0.67

2013             +0.15                          +0.25                                    -0.30

For 1979-2017, there is an 80% chance the ONI value will be within 0.6C of what the formula shows. So let's run some numbers?

October 2018: +0.9 subsurface --> +0.89C ONI, +/- 0.6C (+0.3 to +1.5C). Keep in mind, since 1979, all of the Octobers when the subsurface is over +0.8 have become El Ninos so you have to hedge the odds to the high side of that I think.

October 2018: +1.2 subsurface --> +1.15C ONI, +/- 0.6C (+0.55 to +1.75C). 

October 2018: +1.5 subsurface --> +1.40C ONI, +/- 0.6C (+0.80 to + 2.0C).

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt

Here are all the years between +0.7 and +1.7 in October for the subsurface - 

Year	Month	Subsurf	ONI DJF
1986	10	0.95	0.93
1991	10	1.41	1.32
1994	10	1.12	1.07
2006	10	0.80	0.80
2009	10	1.04	1.01
Analogs	10	1.06	1.03

 

[weathafella]

How do you run analogs of subsurface without a match to ssta ground truth?  I’d want to see that before going forward since it doesn’t matter what subsurface is if it doesn’t translate the same way to the measured ssta.

[raindancewx]

I'm just pulling the numbers from the NOAA site I linked. It is anomalies at 0-300m of depth for Jan 1979 to Sept 2018, for 100-180W. Someone kept referring to their own research about the subsurface predicting things very well, and I could never find the original, so this was my attempt at re-creating it.

There are other zones there that can be tested, but for Nino 3.4, 5S-5N, 120-170W, the 100-180W area seems like the best match. I'm not sure what you mean by matching to SSTA ground truth. The idea with the graph is that the ONI value IS essentially the subsurface, but in the future if that makes sense, pending of course any errors in the correlation which seem to relate to how warm the current surface is. I made ONI against 1951-2010 means to get rid of the noise in the anomalies from the thirty year periods which may have a different number of La Ninas or El Ninos that can be mistaken for "warming" or "cooling". 

The top subsurface matches in the 100-180W zone for 1979-2017 Septembers do match pretty well with the US temperature pattern this month, at least against highs for 1951-2010 which is what I use. 

When I say "it looks warmer" for the subsurface, this is what I mean - the area above the black line and between the yellow lines is the 100-180W subsurface in the link I gave. That entire area is almost completely full of warm anomalies, well up from where it was before in Aug/Sept. The migration of the warmth below the surface is also, at least on net, to the East. Which I why I have a hybrid El Nino, not a Modoki for winter in my forecast.

 

[AfewUniversesBelowNormal]

Notice how there is ridiculous +PNA N Pacific in the next 7 days just as there are subsurface +4 anomalies. 

[raindancewx]

I think some of it is the PDO still isn't really in its warm phase, and Nino 1.2 isn't really warm. Those two seem to go together. The canonical positive PDO should be cold east of Japan, not warm.

In 2014, October looked like a textbook warm PDO month. Historically, the big wet Octobers in the SW are much more common when the PDO in the following Nov-Apr stays near 0, which is what it has been. Right now, we have the northern half of the warm PDO ring, the rest is the cold PDO ring, and then the waters east of Japan, which are warm, are consistent with the cold PDO. The PDO value for Oct 2014 was +1.48. The El Nino actually doe look healthier than the 2014-15 event now which is nice to see. The tremendous warmth along the East Coast is also much higher than in 2014. There is far less warmth along the West Coast too. I'm not a huge fan of 2014-15 as an analog given how different the Pacific is.

 

 

 

[AfewUniversesBelowNormal]

^ You make good points. I'm amazed by the constant +NAO and think it may be indicative of a long term global shift. 

[Great Snow 1717]

18 hours ago, raindancewx said:

I'm just pulling the numbers from the NOAA site I linked. It is anomalies at 0-300m of depth for Jan 1979 to Sept 2018, for 100-180W. Someone kept referring to their own research about the subsurface predicting things very well, and I could never find the original, so this was my attempt at re-creating it.

There are other zones there that can be tested, but for Nino 3.4, 5S-5N, 120-170W, the 100-180W area seems like the best match. I'm not sure what you mean by matching to SSTA ground truth. The idea with the graph is that the ONI value IS essentially the subsurface, but in the future if that makes sense, pending of course any errors in the correlation which seem to relate to how warm the current surface is. I made ONI against 1951-2010 means to get rid of the noise in the anomalies from the thirty year periods which may have a different number of La Ninas or El Ninos that can be mistaken for "warming" or "cooling". 

The top subsurface matches in the 100-180W zone for 1979-2017 Septembers do match pretty well with the US temperature pattern this month, at least against highs for 1951-2010 which is what I use. 

When I say "it looks warmer" for the subsurface, this is what I mean - the area above the black line and between the yellow lines is the 100-180W subsurface in the link I gave. That entire area is almost completely full of warm anomalies, well up from where it was before in Aug/Sept. The migration of the warmth below the surface is also, at least on net, to the East. Which I why I have a hybrid El Nino, not a Modoki for winter in my forecast.

 

I do think your call of a hybrid El Nino is the correct one. Many people are banking on a Modoki El Nino to deliver a good winter but I'm not. 

[Great Snow 1717]

51 minutes ago, AfewUniversesBelowNormal said:

^ You make good points. I'm amazed by the constant +NAO and think it may be indicative of a long term global shift. 

I think it will be interesting to look back in a few years on the NAO. 

[weathafella]

17 minutes ago, Great Snow 1717 said:

I do think your call of a hybrid El Nino is the correct one. Many people are banking on a Modoki El Nino to deliver a good winter but I'm not. 

I think there are examples of not so good winters even with what would appear to guarantee one.  And vice versa.  It’s hard to have a handle because the least predictable element beyond 2 weeks is the nao.  And that could be the difference.   Unless we get episodes of transient blocking even less predictable.

[raindancewx]

As far as the PDO goes, we've had 28 Octobers in 1931-2017 with an inch of rain or more in Albuquerque, like this year when we had 1.64". For 1931-2017, average is 0.85".

18 of those wet Octobers were when the PDO is between -0.5 and +0.5 for the following Nov-Apr. 

Essentially, you have 18/33 years with a neutral PDO see heavy rain in Albuquerque in October, but only 10/54 with a positive or negative PDO do.

As three phases it splits at 6/26 for +PDO, 18/33 for the =PDO, and 4/28 for the -PDO. So you are far more likely to have the PDO between -0.5 and +0.5 when the SW is wet in Oct, and a difference in proportions test indicates it is highly unlikely (~2/1000 odds) to be a fluke.

I'm very interested in seeing what the weeklies show this week. Nino 1.2 on the official CPC/NOAA monthly data set has tended to run warmer than the October weeklies average in Nino 1.2 by around 0.2C over the last 10-years, so I will probably lop on another 0.2C to the four week average in October and then see what my PDO estimator comes up with by blending October Nino 1.2 with the Mar-Aug PDO base state. The blends with the official October Nino 1.2 numbers tend to be +/- 0.4 of the actual Nov-Apr PDO state.

[weathafella]

Per SV, the 10/27 ssta:

enso 1:  0.05

enso 1.2:  0.37

enso 2:  0.70

Enso 3.4:  0.55

Ens 4: 0.93

modoki index: 0.65

If we typically experience the effects in 3 months, we’re basically game over for winter.

 

[raindancewx]

That Modoki index looks like the weekly Modoki Index, which sometimes updates regularly, sometimes not.

http://www.jamstec.go.jp/frcgc/research/d1/iod/DATA/emi.weekly.txt

2018:9:12:0 0.239598
2018:9:19:0 0.575906
2018:9:26:0 0.743502
2018:10:3:0 0.654059

You can get a high Modoki value if Box C, the waters by Australia and the Philippines are cold, since the formula is Box A - (Box B * 0.5) - (Box C * 0.5). Here is a look at El Ninos - for the most recent week, almost every week is close, which is why it is best to look at the three boxes individually, by month/season. My primary analog, 1994-95, shockingly is closest - even though it clearly isn't the correct pattern by itself. If you just went by Modoki values, for just this week, 1997 is least similar...followed interestingly enough by 2014.

1982:10:3:0 0.375299
1986:10:5:0 0.483448
1987:10:4:0 0.439611
1991:10:2:0 0.787229
1994:10:5:0 0.654449
1997:10:8:0 -0.643783
2002:10:2:0 0.716192
2004:10:6:0 0.837429
2006:10:4:0 0.334279
2009:10:7:0 0.521472
2014:10:1:0 0.15739
2015:10:7:0 0.200275

The years in the +0.45 to +0.85 zone are 1986, 1991,1994, 2002, 2004, 2009

[raindancewx]

One good indicator that the PDO isn't positive will be November temperatures nationally. A big positive PDO reading in October tends to shove cold air into the South Central US. I don't see much reason to believe November will be that cold here. I think its near average for highs, but we'll see. Certainly not +8 v. 1951-2010 like last year.

For November I think the middle of the US is near average with the warmth concentrated NW and NE, maybe into CA and the SE too. We'll see what the model runs show in a few days.

[raindancewx]

This is just speculation on my end, but I think 2002 will become vastly less similar to observed conditions this year over the coming months given how different the oceans look in late October.

If you do 2018 - 2002 for 10/26, the El Nino is warmer to the East and colder to the West. The PDO is also less positive with the incredible warmth by Japan, and the tropical Atlantic is very different. The same statements apply v. 2009 - PDO less positive, El Nino is warmer to the East and colder to the West.

The El Nino, at least for now is also much stronger than where 2014 was at this point, but less strong to the east v. 2006. The waters off the Western US are far colder v. 2014 though. The Atlantic is also vastly colder than in 2014 and 2006, with the waters by Japan, once again much warmer.

The very warm waters by Japan are reminiscent of the -PDO. They show up in 2010 for instance.

[BlizzardWx]

11 hours ago, raindancewx said:

This is just speculation on my end, but I think 2002 will become vastly less similar to observed conditions this year over the coming months given how different the oceans look in late October.

If you do 2018 - 2002 for 10/26, the El Nino is warmer to the East and colder to the West. The PDO is also less positive with the incredible warmth by Japan, and the tropical Atlantic is very different. The same statements apply v. 2009 - PDO less positive, El Nino is warmer to the East and colder to the West.

The El Nino, at least for now is also much stronger than where 2014 was at this point, but less strong to the east v. 2006. The waters off the Western US are far colder v. 2014 though. The Atlantic is also vastly colder than in 2014 and 2006, with the waters by Japan, once again much warmer.

The very warm waters by Japan are reminiscent of the -PDO. They show up in 2010 for instance.

From 2007-2013 we had a pretty sustained negative PDO with only a brief positive period during the el nino of 2009/10. Then we had a positive phase for 50 months, from 2014 through March 2018. This summer its been pretty flat and oscillating near zero. Interesting that even during pretty much the entire la nina we maintained a +PDO and only now are seeing some negative months as the next el nino sets in. Hard to say if the somewhat negative PDO look is the result of a few years of la nina trying to erase the mega +PDO and will disappear as el nino builds or if there is actually something driving the -PDO in spite of the developing el nino. Any ideas?

I'd venture that 2002 looked -PDO going into winter because of the 3 year la nina event preceding it, but that look disappeared heading into winter as el nino grew. In some sense we could be in a similar boat here and I wouldn't be shocked to see the -PDO disappear in the next 1-2 months. At least for now though, the waters off of Japan are warming and near the west coast they are cooling. 

 

[raindancewx]

Some of the years in my analogs do have the warmth near Japan, I'm pretty sure 1994 does. I'd actually bet that overall, between Nov-Apr, the PDO finishes between -0.5 and +0.5, which I consider neutral. 

The subsurface warmth is still shifting east. I think that might be why the PDO is all screwed up - El Ninos tend to develop in Nino 1.2 and then spread West. This event is the opposite, so maybe the PDO is really just correlated to how heat moves? We had heat develop West, kind of like a La Nina, but it has moved East, like an El Nino, so the PDO is...neutral.

The weeklies went to moderate levels on the update today.

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 26SEP2018     20.2-0.3     25.5 0.6     27.3 0.6     29.3 0.6
 03OCT2018     21.3 0.7     25.6 0.7     27.4 0.7     29.5 0.8
 10OCT2018     21.1 0.4     25.6 0.7     27.3 0.6     29.5 0.9
 17OCT2018     21.1 0.3     25.9 1.0     27.6 0.9     29.6 0.9
 24OCT2018     21.3 0.3     25.9 1.0     27.7 1.1     29.8 1.1

For whatever reason, the official ONI/CPC monthly data for Nino 1.2 tends to run substantially warmer than Nino 1.2 in October. So I think that zone is at least 21.4C, and my analogs had 21.55C. Depending on what the exact number comes to, I lean pretty heavily toward Neutral for the PDO. The Nino 1.2 + March - August PDO update can be re-created pretty easily from my analogs, and so I remain optimistic. Given how rare wet Octobers are in the SW if the PDO gets to high or too low, I think the safe bet is slightly positive, which is very unlike 2002 and 2014, both of which had the warm ring and cold tongue inside it by now. We have...part of the warm ring and a warm tongue inside it.

[Stebo]

On 10/29/2018 at 7:15 PM, raindancewx said:

Some of the years in my analogs do have the warmth near Japan, I'm pretty sure 1994 does. I'd actually bet that overall, between Nov-Apr, the PDO finishes between -0.5 and +0.5, which I consider neutral. 

The subsurface warmth is still shifting east. I think that might be why the PDO is all screwed up - El Ninos tend to develop in Nino 1.2 and then spread West. This event is the opposite, so maybe the PDO is really just correlated to how heat moves? We had heat develop West, kind of like a La Nina, but it has moved East, like an El Nino, so the PDO is...neutral.

The weeklies went to moderate levels on the update today.

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 26SEP2018     20.2-0.3     25.5 0.6     27.3 0.6     29.3 0.6
 03OCT2018     21.3 0.7     25.6 0.7     27.4 0.7     29.5 0.8
 10OCT2018     21.1 0.4     25.6 0.7     27.3 0.6     29.5 0.9
 17OCT2018     21.1 0.3     25.9 1.0     27.6 0.9     29.6 0.9
 24OCT2018     21.3 0.3     25.9 1.0     27.7 1.1     29.8 1.1

For whatever reason, the official ONI/CPC monthly data for Nino 1.2 tends to run substantially warmer than Nino 1.2 in October. So I think that zone is at least 21.4C, and my analogs had 21.55C. Depending on what the exact number comes to, I lean pretty heavily toward Neutral. The Nino 1.2 + March - August PDO update can be re-created pretty easily from my analogs, and so I remain optimistic. Given how rare wet Octobers are in the SW if the PDO gets to high or too low, I think the safe bet is slightly positive, which is very unlike 2002 and 2014, both of which had the warm ring and cold tongue inside it by now. We have...part of the warm ring and a warm tongue inside it.

Some of the coastal trends within the PDO region are trending cooler which would be more favorable of a negative PDO.

[raindancewx]

The PDO has a way of signalling where cold air ends up in El Nino years for what its worth, so the exact value doesn't matter too much, but the +/=/- sign does matter. For the SW it is only a precipitation signal, but for other areas it is more of a temperature signal.

A lot of years have part of the October SST look this year, 2006, 2004, 1994, 1991, 1930 as some kind of blend might be closest. Will be interested to see what the PDO value is for October. 2004 by itself is probably closest, then 1994, then 1930. A blend of 1997, 2004, 2005, 2013 isn't half bad honestly for the North Pacific.

 

[raindancewx]

If Nino 3.4 ends up around +1.0C above the 1951-2010 mean of 26.5C in DJF, the transition from last winter (DJF) will be most similar to 1963, 1965, 1968, 2006 nationally - and three of those years feature low solar. If you weight 2006 heavily in the blend, those years are a good mix for my "PDO Method", where you need similar Mar-Aug PDO numbers to the current year, and Oct Nino 1.2 SSTs. Using the similar Nino 3.4 transition implies a slightly negative, but still "Neutral" PDO, which is somewhat consistent with the warming waters by Japan and the cooling waters where the super waters are near Alaska.

[griteater]

Nino 3.4 jumped up from +0.54 on Oct28 to +0.98 on Oct29 on the daily AVHRR SST data, which is more in line with NOAA's recent weekly reading of +1.1.  Lots of warmth shown here up and down the central to central-west Pacific (top image).  Warmest temps in the warm pool are located just west of the dateline (bottom image)

[raindancewx]

^^ My theory with Tropical Tidbits is he uses the monthly average for each six hour SSTA reading in Nino 3.4, even though some other data sets use daily or weekly readings for more precise calibration, which is why the readings tend to go up or down a lot when the calendar flips, i.e. the Nino magically appeared in Oct on his site, but it showed up around 9/20-9/25 on the other data sets.

The "Raindance Rule" is now in effect for March: Albuquerque has (FINALLY) had a wet August & October in 2018. When Albuquerque has 2.7" or more in August & October, you approach near certainty of snow in ABQ in March, and it holds true to a lesser extent even in areas to the south and at low elevations. For Albuquerque, years with >=2.7" see snow the following March 27/29 times, all other years (58) are about 55% odds for snow in March. The city has not had a wet March against 1951-2010 means since 2007, and that is also favored when Aug & Oct are wet, and the last time the Aug+Oct period was wet was in 2006, prior to our last wet March.

Things that tend to happen when the "Raindance Rule" is in effect, include major hurricanes hitting the Gulf of Mexico (1941, 1957, 1965, 1969, 2004, TX, Audrey, Betsy, Camille, and Ivan) if August is dry in Albuquerque, but October is wet, and you have an El Nino. Those years average around six inches of snow here, against the long-term average of 1.5". Main issue is that level of snow almost never happens (1/33 tries) with low solar activity (<=55 sunspot average for July-Jun).

1957 and 2004 are top-ten SOI analogs for July-Oct (pending 10/31) as well.

SOI    July    Aug    Sept    Oct    ABS
2018    1.8    -6.7    -8.5    2.3    0.0
1957    1.4    -8.2    -9.4    -0.3    5.4
1986    2.0    -7.0    -4.7    6.6    8.6
1948    0.8    -4.0    -7.1    6.6    9.4
1990    5.2    -4.4    -7.3    -1.2    10.4
2012    0.1    -6.2    3.2    2.3    13.9
1952    4.5    -2.2    -1.8    3.5    15.1
1936    3.9    -8.2    2.9    0.3    17.0
1980    -1.6    1.5    -4.7    -0.9    18.6
2004    -6.4    -6.7    -3.2    -3.0    18.8
1932    1.1    4.9    -8.3    -4.1    18.9

[griteater]

10 hours ago, griteater said:

Nino 3.4 jumped up from +0.54 on Oct28 to +0.98 on Oct29 on the daily AVHRR SST data

Nino 3.4 is up to +1.23 on the Oct30 reading.  Modoki index up to +1.03.  I realize that ENSO is best viewed over a monthly to several months time period, but I'm just reporting the daily numbers.

[40/70 Benchmark]

1 hour ago, griteater said:

Nino 3.4 is up to +1.23 on the Oct30 reading.  Modoki index up to +1.03.  I realize that ENSO is best viewed over a monthly to several months time period, but I'm just reporting the daily numbers.

This a modoki, plain and simple. Sure, its not going to an extreme 2009 modoki, but I hear some trying to qualify it as "hybrid"...whatever. Its a modoki, just as most modest + ENSO events are. 

You can get into trouble trying to be to cute and qualifying every event that does not fall on an extreme end of the modoki value spectrum. This happened to me with the 2015 super el nino....it was not as extremely east based as 1997 and 1982, so I went the hybrid route, and got burned. The only aspect of that outlook that I salvaged was the mid atlantic blizzard.

It doesn't need to be 2009 to be a modoki. 

This is not 2006.

At the end of the day, the location of the warmest sst anomalies are aligned much more closely with 2009 than they are 1997.

[Typhoon Tip]

Could also be that we arrived into a new world where warmth pervades like, everywhere ...  Perhaps it merely is not "normal" because it has not existed long enough yet to move the 30 year norms... 100 years...etc.  If we are comparing a new base-line against an old one, that makes the usefulness less dependable. 

Remember, we're looking for "anomalies" to define eras of cool and warm ENSO states. 

Anomaly is generally determined via standard deviation ...in statistical mathematics, which means, find the mean... Subtract the events of the data set from the mean, square each result, ... find that mean, then, determine it's square root.    See that word 'mean' popping up in there as the recurrent variable? 

Just keep in mind .. if the mean is no longer fixed in time, ...  Put it this way, it may be useful to ask if those products that display the present states of the ENSO are normalized to account for a changing system.   

I think one of the papered reasons why the big recent El Nino did not register "as many" more typical global impacts of warm ENSO ... particularly considering it's own extremeness, is related to a system where the warmth/extent may be getting skewed by a steadily less validating comparison

[AfewUniversesBelowNormal]

You know, to be honest, I didn't really believe ENSO impacted the North Pacific until this El Nino. It's been interesting to watch a strong pattern of 10-15 years shattered around this time. OLR has shifted too. 

[raindancewx]

When I say hybrid El Nino, what I mean is you don't have the area of most unusual warmth right by Peru, and you don't also have it in Nino 3.4/4 surrounded by colder waters to the east/west like in an idealized Modoki. For October it looks like the warmest anomalies are not to where 1972/1982/1997 got warmest, but certainly well to the East of an idealized Modoki pattern, around 120W, not around 170W. If anything it looks closer to the 1972/1982/1997 pattern (not strength, location) at least for October. The warm ideas you see on the CFS and some of the other models is consistent with the East-Central or hybrid idea more than the Modoki idea, and it seems to be based on the subsurface warmth slowly sloshing east and up to the surface. 

We'll see what the Canadian and European updates show soon (tonight for the Canadian?) but the CFS has this now -

 

My analogs had the Nino structure similar to Oct of this year, so I think I'm on the right track. The very heavy rain in the SW showed up in almost every analog, we're at two inches in Albuquerque, over double the long-term average, pretty rare and hard to achieve without some special things in place globally.

[raindancewx]

The Canadian has shifted to a stronger, longer-lasting, and more-east centered El Nino.

The trend was colder for TX, warmer or flat for much of the US.

The model has most of the US near average for precipitation. In addition to showing the SE wet, it now has the NW wet too, maybe seeing the -PDO?

Here is a look at how well the Canadian did last year for temps from 10/31 - I'd give it a C+. It had most of the US warm, main issues were intensity in the mid-south and TX for the heat, and some areas of the NW/Plains for the cold.

 

[40/70 Benchmark]

13 hours ago, raindancewx said:

The Canadian has shifted to a stronger, longer-lasting, and more-east centered El Nino.

The trend was colder for TX, warmer or flat for much of the US.

The model has most of the US near average for precipitation. In addition to showing the SE wet, it now has the NW wet too, maybe seeing the -PDO?

Here is a look at how well the Canadian did last year for temps from 10/31 - I'd give it a C+. It had most of the US warm, main issues were intensity in the mid-south and TX for the heat, and some areas of the NW/Plains for the cold.

 

Canadian looks slightly colder and wetter for the northeast to me.

[OSUmetstud]

28 minutes ago, 40/70 Benchmark said:

Canadian looks colder for the northeast to me.

Feb looks a ton better than the previous run but as a whole it the anomalies are similar. 

I think the general look is a bit weird after December. The PAC slp and 500mb anomalies dont look particularly nino like even though the SST and convection is there. 

 

 

[40/70 Benchmark]

Feb looks more traditional NAO now, whereas last month it appeared east based.

Its a better run, regardless of ENSO nuances.

Great modoki pattern in the east.

Thanks for posting that, raindance.