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Pattern ENSO Updates

Today's SOI rose from yesterday's ~-25, the lowest since Feb., to today's ~-15. I'm expecting tomorrow's SOI to be a small positive due to a significant SLP fall at Darwin and a rise at Tahiti.

The 0Z Euro indicates no return to the solid -SOI area at least for 10 days. It suggests no Darwin SLP above 1013 and mainly near the 1011.5-1012.5 range while Tahiti daily appears to mainly hang around the 1014-15 range. That would mean an average of near a +5 SOI for the upcoming 10 days (no SOI below the negative single digits), which is in contrast to the -7 averaged over the last 17 days. Based on this, we should end up pretty close to 0 for the first 17 days of May. So, from a potential oncoming El Nino standpoint, the May SOI so far isn't looking gung ho on it though we need to remember that the subsurface is pretty warm. Also, looking at history back to the late 1800s, weak to moderate El Ninos have often had pretty neutral to sometimes even solidly +s in preceding May SOIs. So, it is still too early to read much into the SOIs as far as weak to moderate El Nino chances are concerned. The summer SOIs will give us a bigger hint.

However, the 6 strongest Ninos had these preceding May SOIs: -7.0, -8.5, -24.0, -7.1, -19.0, and -13.1 or an average of -13.1. So, this tells me that a very strong El Nino isn't currently being suggested by the 5/2018 SOI.
 
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Since monthly upper equatorial Pacific OHC (subsurface) records started in 1979, here are the 10 warmest Aprils (180-100W) prior to 2018:

1997: +2.17
2015: +1.74
2014: +1.41
1982: +0.93
1980: +0.82
1993: +0.81
1991: +0.80
1981: +0.77
2009: +0.65
1990: +0.65

6 of these 10 as well as the four warmest (+0.93+) preceded El Nino. The other 4 preceded neutral ENSO. So, none preceded La Nina.

April of 2018 just came out and was +0.81, which is tied with April of 1993 for 6th warmest out of 40! Although it is impressively warm and should be taken into account for El Nino chances, this 0.81 is not warm enough to give me high confidence in an oncoming El Nino based strictly on the above stats as three that were nearby (1980's +0.82, 1993's +0.81 and 1981's +0.77) turned out to precede neutral ENSO falls/winters. 1993 turned out to be a major El Nino fake-out, much more misleading than 2017.

***Edit: Of Aprils of 1980, 1981, and 1993, 2 of the 3 cooled a lot the very next month. So, the May OHC may be a good hint of what's to come.

Monthly upper OHC link: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt
 
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GaWx said:
Since monthly upper equatorial Pacific OHC (subsurface) records started in 1979, here are the 10 warmest Aprils (180-100W) prior to 2018:

1997: +2.17
2015: +1.74
2014: +1.41
1982: +0.93
1980: +0.82
1993: +0.81
1991: +0.80
1981: +0.77
2009: +0.65
1990: +0.65

6 of these 10 as well as the four warmest (+0.93+) preceded El Nino. The other 4 preceded neutral ENSO. So, none preceded La Nina.

April of 2018 just came out and was +0.81, which is tied with April of 1993 for 6th warmest out of 40! Although it is impressively warm and should be taken into account for El Nino chances, this 0.81 is not warm enough to give me high confidence in an oncoming El Nino based strictly on the above stats as three that were nearby (1980's +0.82, 1993's +0.81 and 1981's +0.77) turned out to precede neutral ENSO falls/winters. 1993 turned out to be a major El Nino fake-out, much more misleading than 2017.

***Edit: Of Aprils of 1980, 1981, and 1993, 2 of the 3 cooled a lot the very next month. So, the May OHC may be a good hint of what's to come.

Monthly upper OHC link: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt
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Larry,
Good info and a great link; please take a minute and look at Wiki and let me know if you'd like the link placed there, and if so, where; in that case I'll add it.
Best!
Phil
 
pcbjr said:
Larry,
Good info and a great link; please take a minute and look at Wiki and let me know if you'd like the link placed there, and if so, where; in that case I'll add it.
Best!
Phil
Click to expand...

I didn't see an ENSO section. Maybe I missed it. If you were to start one, I'd put it in there. Otherwise, I wouldn't put it in the wiki.
 
GaWx said:
I didn't see an ENSO section. Maybe I missed it. If you were to start one, I'd put it in there. Otherwise, I wouldn't put it in the wiki.
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Here ya go - Just created it.
http://wiki.southernwx.com/doku.php?id=learning_materials
FS and I need to get a dedicated page to ENSO stuff, or get links and models into an ENSO section under "Models" with stuff like you provide. I'd prefer the latter in Models, but it may not fit (???).
Thoughts?
Best,
Phil
 
pcbjr said:
Here ya go - Just created it.
http://wiki.southernwx.com/doku.php?id=learning_materials
FS and I need to get a dedicated page to ENSO stuff, or get links and models into an ENSO section under "Models" with stuff like you provide. I'd prefer the latter in Models, but it may not fit (???).
Thoughts?
Best,
Phil
Click to expand...

I'd have a section covering items used to predict oncoming ENSO. This can include ENSO prediction models. But I wouldn't call the section "models".
 
@pcbjr I need to explain further. I use current indices/indicators like SOI, OHC, SST anomalies, and other things to try to predict the following fall/winter ENSO. They're somewhat predictive based on the multidecadal+ history of each indicator. But since these aren't models, I wouldn't call the section "Models". Instead, I'd call the section, which certainly could include ENSO models, something like "Indicators used to predict ENSO". I also look at the ENSO models but not as frequently.

Maybe I'll provide to you at some point when I have more time a list of some of the other links I use that can go in this section.
 
GaWx said:
@pcbjr I need to explain further. I use current indices/indicators like SOI, OHC, SST anomalies, and other things to try to predict the following fall/winter ENSO. They're somewhat predictive based on the multidecadal+ history of each indicator. But since these aren't models, I wouldn't call the section "Models". Instead, I'd call the section, which certainly could include ENSO models, something like "Indicators used to predict ENSO". I also look at the ENSO models but not as frequently.

Maybe I'll provide to you at some point when I have more time a list of some of the other links I use that can go in this section.
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Whatever we do and whenever, I just want it to be right ... Thanks, Larry! ... ;)
 
I'll take neutral heading into fall/ winter. 1st choice is weak el Nino. And I mean weak, hair above neutral.
 
NCSNOW said:
I'll take neutral heading into fall/ winter. 1st choice is weak el Nino. And I mean weak, hair above neutral.
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Wasn't 2009-10 a moderate El Nino? I was thinking it was on the border line between weak and moderate. I just hope we don't have another La Nina or even cool neutral.
 
cd2play said:
Wasn't 2009-10 a moderate El Nino? I was thinking it was on the border line between weak and moderate. I just hope we don't have another La Nina or even cool neutral.
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It peaked at low end strong.
 
Latest ENSO discussion says no El Niño Advisory but nearly 50% chance of a El Niño by DJF.
 
Snowfan said:
Latest Nino 3.4 update is the same from last update.
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Indeed, Niño 3.4 stays at -0.1C:

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

Note in this update that the upper equatorial Pacific OHC is not only holding up but it is starting to slowly rise again and is back above +0.80. If this persists into June, the chance at a weak to possibly moderate El Niño peak in late fall or winter would increase.

At the same time, I have just learned about a 0.5 C warm bias in the May Eurosip ASO Niño 3.4 forecast based on 13 years of data. Therefore, I eagerly await the release of the May 2018 Eurosip ASO Niño 3.4 forecast. If it were to come in at only warm neutral, I'd have to favor no warmer than warm neutral for at least ASO even though it could subsequently reach weak El Niño later in the year. Even if it were to come in at weak El Niño in ASO, I'd have to remain wary about it happening as early as ASO due to this 0.5 C warm bias. Sometimes Eurosip has gotten this right but more often it has missed to the warm side. Then again, a persistently warm upper OHC may mean this would be one of the times Eurosip gets it right.
 
The May, 2018, Eurosip ENSO 3.4 SST anomaly forecast through October was released today:

https://stream.ecmwf.int/data/gorax...7-6fe5cac1a363ec1525f54343b6cc9fd8-2H4fDD.png

I have it near +0.35 or warm neutral rather than weak El Nino for ASO averaged out. Based on what I've found to be a significant warm bias in the Eurosip, I'm now expecting no warmer than warm neutral for ASO despite a solidly warm subsurface that is now starting to rewarm slowly. Because of this warm bias and because we're still cold neutral, I can't yet count out cold neutral for ASO though I'm thinking warm neutral has the best chance right now due to the warm subsurface and since 5 of the 13 Eurosip forecasts turned out accurate. I still think it MAY get to weak to possibly low end moderate El Nino status by late fall or early winter, especially if the warm subsurface holds or warms.

I found this warm bias by looking at how the ASO 3.4 SST anomaly forecasts made in the preceding May by Eurosip verified:

Year: Eurosip's May fcast verification for ASO 3.4
2017: 1.1 cooler (cold neutral occurred vs weak El Niño prediction)
2016: 0.1 warmer (weak La Niña correctly predicted)
2015: 0.1 warmer (strong El Niño correctly predicted)
2014: 0.5 cooler (warm neutral occurred vs weak El Niño prediction)
2013: 0.5 cooler (cold neutral occurred vs warm neutral prediction)
2012: 0.9 cooler (warm neutral occurred vs moderate El Niño prediction)
2011: 1.1 cooler (moderate La Niña occurred vs warm neutral prediction)
2010: 0.9 cooler (strong La Niña occurred vs weak La Niña prediction)
2009: 0.2 cooler (weak El Niño correctly predicted)
2008: 0.8 cooler (cold neutral occurred vs weak El Niño prediction)
2007: 0.2 cooler (moderate La Niña correctly predicted)
2006: 0.2 cooler (weak El Niño correctly predicted)
2005: 0.4 cooler (cold neutral occurred vs warm neutral prediction)

So, of the 13 May forecasts for ASO, 5 were correctly predicted while 3 were one category too warm, 4 were two categories too warm, and 1 was three categories too warm. None were any categories too cold! The average was 0.5 too warm or one category too warm.

Out of the 7 Eurosip El Niño predictions for ASO in the preceding May, only 3 verified. In contrast, Eurosip predicted only 3 La Niñas in ASO but 4 occurred.

Of the 3 warm neutral predictions, 2 ended up one category too warm while 1 ended up three categories too warm. Of the 5 weak El Niño predictions, 2 ended up verifying correctly while 1 was one category too warm and 2 were two categories too warm.

Out of the 13 predictions, weak El Niño was clearly the most common prediction (5) while warm neutral was 2nd most common (3). Next was weak La Niña (2). The remainder were each predicted once: strong El Niño, moderate El Niño, and moderate La Niña. There were no cold neutral or strong La Niña predictions though 4 cold neutral occurred (the most of any category) and one strong La Niña occurred.

So, of the 13 May predictions for ASO, a whopping 10 were warmer than 0.0 while only 3 were colder. It turned out that only 5 were warmer than 0.0 while 8 were colder.

The average May Eurosip ASO 3.4 prog during 2005-17 was for +0.4 vs the -0.1 actual.
 
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