ENSO Updates (2007 thru 2023)

[NDG]

:uarrow: Yeah,the WPAC has been very quiet in the past month and a half but with the forecast of a strong pulse soon,things will turn active in that basin.

Note=SOI reached La Nina threshold of +8.

And when the wet MJO reaches the eastern South Paacific near Tahiti, and thus placing the dry MJO over Australia, would mean that the SOI will tank a lot later on, but not now. Wet MJO means lower pressure, while the opposite happens with dry MJO, and thus if the Wet MJO is over Tahiti, while the dry MJO over Darwin brings higher pressure over there, bringing us to negative SOI readings.

By the looks of it is going to be a while before the wet phase of the MJO gets to the central and eastern Pacific.

[cycloneye]

Climate Prediction Center June update

They say El Nino chance is 70% by Summer and 80% by the Fall/Winter but uncertainty remains about how strong it will be.

EL NIÑO/SOUTHERN OSCILLATION (ENSO)
DIAGNOSTIC DISCUSSION
issued by
CLIMATE PREDICTION CENTER/NCEP/NWS
and the International Research Institute for Climate and Society
5 June 2014


ENSO Alert System Status: El Niño Watch



Synopsis: The chance of El Niño is 70% during the Northern Hemisphere summer and reaches 80% during the fall and winter.

Above-average sea surface temperatures (SST) expanded over the equatorial Pacific Ocean during May 2014 (Fig. 1), though the collective atmospheric and oceanic state continued to reflect ENSO-neutral. All of the Niño indices increased during the month, with the latest weekly values between 0.6oC and 1.6oC (Fig. 2). In contrast, subsurface temperature anomalies decreased over the last two months (Fig. 3), but still reflect a large pool of above-average temperatures at depth (Fig. 4). The low-level winds over the tropical Pacific remain near average, except for westerly anomalies over the eastern Pacific. At upper-levels, anomalous easterly winds have predominated over most of the equatorial Pacific. Unlike the previous month, convection was near average across most of the tropics (Fig. 5). The lack of a clear atmospheric response to the positive SSTs indicates ENSO-neutral, though the tropical Pacific continues to evolve toward El Niño.

Over the last month, the chance of El Niño and its ultimate strength weakened slightly in the models (Fig. 6). Regardless, the forecasters remain just as confident that El Niño is likely to emerge. If El Niño forms, the forecasters and most dynamical models, such as NCEP CFSv2, slightly favor a moderate-strength event during the Northern Hemisphere fall or winter (3-month values of the Niño-3.4 index between 1.0oC and 1.4oC). However, significant uncertainty accompanies this prediction, which remains inclusive of a weaker or stronger event due to the spread of the models and their skill at these lead times. Overall, the chance of El Niño is 70% during the Northern Hemisphere summer and reaches 80% during the fall and winter. (click CPC/IRI consensus forecast for the chance of each outcome)



http://www.cpc.ncep.noaa.gov/products/a ... odisc.html

[xtyphooncyclonex]

:uarrow: Yeah,the WPAC has been very quiet in the past month and a half but with the forecast of a strong pulse soon,things will turn active in that basin.

Note=SOI reached La Nina threshold of +8.

And when the wet MJO reaches the eastern South Paacific near Tahiti, and thus placing the dry MJO over Australia, would mean that the SOI will tank a lot later on, but not now. Wet MJO means lower pressure, while the opposite happens with dry MJO, and thus if the Wet MJO is over Tahiti, while the dry MJO over Darwin brings higher pressure over there, bringing us to negative SOI readings.

By the looks of it is going to be a while before the wet phase of the MJO gets to the central and eastern Pacific.

Yup. We have to wait a while before the MJO arrives and for the SOI would tank. The SOI is even rising more...

[cycloneye]

Good discussion by WSI about the next WWB.

A strong Madden Julian Oscillation event is forecast to develop over the central-eastern Pacific later this month in through early July. This MJO-location favors for another period of westerly wind bursts over the central part of the Pacific Basin, an atmospheric signature that is likely to be the final kick needed for a blossoming El Nino event.

http://www.wsi.com/blog/energy/el-nino- ... -imminent/

[euro6208]

Indeed, latest forecast has a moderate MJO over the Maritime Continent and either a moderate or strong event in the WPAC if it continues developing which will likely enhance cyclone genesis over the area before spreading eastwards and deepens el nino...

[NDG]

While you guys wait for the forecasted stronger phase of the MJO the SOI Index continous to go up, +10.2, there's probably going to be some cooling taking place soon at Niño 3.4 and continue warming in the western Pacific, at least temporarily, IMO.

SOI Index

[xtyphooncyclonex]

While you guys wait for the forecasted stronger phase of the MJO the SOI Index continous to go up, +10.2, there's probably going to be some cooling taking place soon at Niño 3.4 and continue warming in the western Pacific, at least temporarily, IMO.

SOI Index

There is a cooling as proven in the daily data in all Niño regions, but we will later see some rapid warming over the Niño regions. And now, the SOI is consistently positive.

[xtyphooncyclonex]

Surprisingly, the MAM ONI calculation is only at -0.2. If MAM was mostly positive, why is the index negative? I calculated the average and it was at positive. And is the ONI calculation of only Niño 3.4 or all regions? I'm quite confused.

[cycloneye]

A difference between May of 1997 and May of 2014. New strong WWB event is needed to reinforce the actual warm pool. And the SOI has to fall in line too but right now is in La Nina threshold.

[xtyphooncyclonex]

A better event to compare this year's El niño is 1982, if not, 1991 or 2009. May to early or mid June 2014 is in the dry MJO state over the Pacific, meaning not much warming, if not cooling has been happening, so things will change when the wet MJO will arrive and many people will exaggerate about the strength, and will go for a stronger Niño, and now when it is at the dry MJO state, many people also exaggerate about this being weak. So yeah, I would be sticking with a 1982-1991-2009 hybrid with a few resemblances with the 1997 and 1972 events.

https://bobtisdale.wordpress.com/2014/06/03/the-201415-el-nino-part-10-june-2014-update-still-waiting-for-the-feedbacks/

[xtyphooncyclonex]

A difference between May of 1997 and May of 2014. New strong WWB event is needed to reinforce the actual warm pool. And the SOI has to fall in line too but right now is in La Nina threshold.

Yep. There is another one coming in the latter part of this month, which could probably lead to a sharp rise to the anomalies over the equatorial Pacific. That could help in the El Niño development and could favor a declaration later this month.

[dexterlabio]

I don't know with you guys but I think 1991 or 2009 is now the closest analog for this year's EN, not the years like 1982 and 1997. And I still don't think the warming will fizzle out like in 2012...PDO was very negative that year and the warming couldn't be sustained because of cooler water west of N. America.

[Yellow Evan]

I don't know with you guys but I think 1991 or 2009 is now the closest analog for this year's EN, not the years like 1982 and 1997. And I still don't think the warming will fizzle out like in 2012...PDO was very negative that year and the warming couldn't be sustained because of cooler water west of N. America.

1991 and 2009 were modoki's at some point, but I agree.

[Alyono]

dont count on a TC enhances WWB. GFS has been consistently cranking out TCs in the WPAC, but they have not been occurring. In addition, the TCs are depicted at 20N... too far north to enhance the equatorial westerlies

[cycloneye]

If 94E turns into a powerful hurricane will it create WWB to enhance warming or is too far from equator?

[Ntxw]

Surprisingly, the MAM ONI calculation is only at -0.2. If MAM was mostly positive, why is the index negative? I calculated the average and it was at positive. And is the ONI calculation of only Niño 3.4 or all regions? I'm quite confused.

I'm a little perplexed too. I've gone over their weekly readings and it never adds up. Instead of the -0.2, every method I try instead comes up with 0.2. Unless they calculate it using something else other than their weekly readings I have no idea what they are doing. The other months seemingly adds up fine using their weeklies but MAM is different so something there is not consistent.

[cycloneye]

Here is a interesting discussion that Levi Cowan made at WU about how things are not working in a uniform way to promote El Nino right away.

It is intriguing to ponder why the atmosphere can "resist" an El Nino state, such as it is doing right now. Sometimes this happens even when it was a WWB that drove the initial warming of the equatorial Pacific in the first place. The atmosphere and ocean may be coupled, but they can fight each other, and what causes them to fight instead of cooperate is a fascinating question.

This year, it may be the incredible warmth of the Indian Ocean and western Pacific relative to a typical El Nino. Usually those waters are much colder than they are right now when an El Nino is developing, and this may be throwing a monkey-wrench into the inverted Walker Circulation that El Nino typically promotes.

[Ntxw]

Here is a interesting discussion that Levi Cowan made at WU about how things are not working in a uniform way to promote El Nino right away.

It is intriguing to ponder why the atmosphere can "resist" an El Nino state, such as it is doing right now. Sometimes this happens even when it was a WWB that drove the initial warming of the equatorial Pacific in the first place. The atmosphere and ocean may be coupled, but they can fight each other, and what causes them to fight instead of cooperate is a fascinating question.

This year, it may be the incredible warmth of the Indian Ocean and western Pacific relative to a typical El Nino. Usually those waters are much colder than they are right now when an El Nino is developing, and this may be throwing a monkey-wrench into the inverted Walker Circulation that El Nino typically promotes.

I have wondered if the warming Indian Ocean (it's the been warming the most of the 3 big equatorial oceans) plays any role in masking ENSO events. It's not something I have much knowledge about other than the fact that that ocean climo wise has risen the most of the three.

[dexterlabio]

Here is a interesting discussion that Levi Cowan made at WU about how things are not working in a uniform way to promote El Nino right away.

It is intriguing to ponder why the atmosphere can "resist" an El Nino state, such as it is doing right now. Sometimes this happens even when it was a WWB that drove the initial warming of the equatorial Pacific in the first place. The atmosphere and ocean may be coupled, but they can fight each other, and what causes them to fight instead of cooperate is a fascinating question.

This year, it may be the incredible warmth of the Indian Ocean and western Pacific relative to a typical El Nino. Usually those waters are much colder than they are right now when an El Nino is developing, and this may be throwing a monkey-wrench into the inverted Walker Circulation that El Nino typically promotes.

I remember some posts months ago comparing the SST maps of 1997 and 2014...at some point, yes, there was a resemblance but the warm water stuck east of PI this year is where the difference lies. I think I pointed it out before but I was thinking that it wouldn't matter too much...

Right now, the waters in the South China Sea and WPAC are just as warm, if not warmer, than the waters in far eastern Pacific. If I'm not mistaken, we need another round of strong WWB (or a strong, fast-moving MJO) to transport the warmth towards the east to get this Nino going...

[Ntxw]

I remember some posts months ago comparing the SST maps of 1997 and 2014...at some point, yes, there was a resemblance but the warm water stuck east of PI this year is where the difference lies. I think I pointed it out before but I was thinking that it wouldn't matter too much...

Right now, the waters in the South China Sea and WPAC are just as warm, if not warmer, than the waters in far eastern Pacific. If I'm not mistaken, we need another round of strong WWB (or a strong, fast-moving MJO) to transport the warmth towards the east to get this Nino going...

Waters in the WPAC are always warmer than in the east Pacific even in El Nino. This is why in several posts I mentioned sometimes you have to put aside the "anomalies" to grasp what ENSO is. El Nino is when the eastern basin warms up from it's typical cold climo to warmer than it is normally, not necessarily warmer than the wpac. An anomaly is based on what it is against climo not against the wpac.