2024 ENSO Updates= BoM / CPC have La Niña watch in effect

[cycloneye]

Both the 30 day and 90 day SOI are going up.

[NotSparta]

Excuse any ignorance on my part but what is going on with 7 day trend in the Nino region of the Pac?
Seems unexpected or no?
https://i.imgur.com/CfjHuiY.png

You tend to get wild fluctuations during the transition to La Nina as the cooler waters attempt to flush out the remaining warm water. This is about as expected as it gets

[cycloneye]

CPC reaches the important line of +0.5C and is very probable that they will say el niño ends on next thursdays update.

https://www.cpc.ncep.noaa.gov/products/ ... ts-web.pdf

[LarryWx]

CPC reaches the important line of +0.5C and is very probable that they will say el niño ends on next thursdays update.

https://www.cpc.ncep.noaa.gov/products/ ... ts-web.pdf

https://i.imgur.com/kzKhTOU.jpeg

https://i.imgur.com/eOFS1PD.jpeg

From a relative (RONI) basis, it is probably already down to at least near 0.0.

[cycloneye]

 https://twitter.com/dmorris9661/status/1788003182318071847

[cycloneye]

I say there is 100% chance, that El Niño will end officially tommorow, when CPC makes the announcement in the may update.

[cycloneye]

El NIño hangs on for one more month and then comes Neutral and in a fast pace, La NIña afterwards.

https://www.cpc.ncep.noaa.gov/products/ ... disc.shtml

A transition from El Niño to ENSO-neutral is likely in the next month. La Niña may develop in June-August (49% chance) or July-September (69% chance).

During April 2024, below-average equatorial sea surface temperatures (SSTs) emerged in small regions of the eastern Pacific Ocean. However, above-average SSTs prevailed across the rest of the equatorial Pacific [Fig. 1]. The latest weekly Niño index values remained between +0.5°C and +0.8°C in all regions, except for Niño-3 which was +0.3°C [Fig. 2]. Below-average subsurface temperatures held steady during the month (area-averaged index in [Fig. 3]), with negative anomalies extending from the Date Line to the eastern Pacific Ocean [Fig. 4]. Low-level wind anomalies were easterly over the western equatorial Pacific, while upper-level winds were near average. Convection was near average overall across the equatorial Pacific Ocean and Indonesia [Fig. 5]. Collectively, the coupled ocean-atmosphere system reflected the continued weakening of El Niño and transition toward ENSO-neutral.

[StPeteMike]

Surprise they held onto El Niño for a little bit longer but there’s a reason they’re the experts and I’m just an observer. haha

[Category5Kaiju]

Farewell El Nino! I guess we'll see you again in....2026 or 2027? Maybe 2028 at the latest?

[cycloneye]

There were discussions among the CPC folks about to end el niño in this update or not. See below about that at their ENSO Blog:


https://www.climate.gov/news-features/b ... te-were-10

There was some discussion this week amongst our ENSO forecast team about whether El Niño, much weakened already early last month, is still present. El Niño is a coupled system, meaning the ocean and atmosphere both exhibit characteristic changes. The atmospheric half of El Niño is harder to detect this month; most of the standard equatorial Pacific atmospheric indicators (rain and clouds over the tropical Pacific, trade winds and upper-level winds) were pretty close to average.

However, the April average sea surface temperature in the tropical Pacific was still 0.8 °C above average according to the ERSSTv5 dataset (average = 1991–2020). The latest weekly measurement, which comes from the OISSTv2 dataset, was 0.5 °C above average. Given that the El Niño threshold is 0.5 °C, the team decided we’re right on the edge of the transition to neutral conditions. We also can’t rule out some lingering El Niño impacts in other regions of the world.

[Teban54]

There were discussions among the CPC folks about to end el niño in this update or not. See below about that at their ENSO Blog:


https://www.climate.gov/news-features/b ... te-were-10

There was some discussion this week amongst our ENSO forecast team about whether El Niño, much weakened already early last month, is still present. El Niño is a coupled system, meaning the ocean and atmosphere both exhibit characteristic changes. The atmospheric half of El Niño is harder to detect this month; most of the standard equatorial Pacific atmospheric indicators (rain and clouds over the tropical Pacific, trade winds and upper-level winds) were pretty close to average.

However, the April average sea surface temperature in the tropical Pacific was still 0.8 °C above average according to the ERSSTv5 dataset (average = 1991–2020). The latest weekly measurement, which comes from the OISSTv2 dataset, was 0.5 °C above average. Given that the El Niño threshold is 0.5 °C, the team decided we’re right on the edge of the transition to neutral conditions. We also can’t rule out some lingering El Niño impacts in other regions of the world.

This is where I wonder if controlling for global warming and the rest of the global SSTs should have been used, such as relative ONI (RONI) as Larry had advocated for recently. Even with 1991-2020 climo, it feels that the much warmer global oceanic pattern is at least hurting the atmospheric coupling of this El Nino, if not outright inflating ONI.

[Kingarabian]

I think one of the reasons they kept the El Nino is probably due to the 90 day SOI still in warm ENSO mode.

In 2019, one of their reason to not extend the 2018 El Nino is because the ONI was going to update later in 2019 nd that the trimonthlies would be automatically adjusted lower. Which didn't happen. So I don't think the CPC relies solely on ONI or RONI in their assessments. The CPC has said it factors in all of the avaliable Climo datasets and also factors buoy and ship data in their Nino estimates. So they're probably seeing something we don't have access to.

That being said the El Nino event is over and we're just waiting on cool neutral conditions to set in. Very possible we see a La Nina before August.

[cycloneye]

 https://twitter.com/TylerJStanfield/status/1788582295877624218

[ColdMiser123]

May 8th OISSTv.2.1 SST departures, which should be used in this Monday's CPC update:

Niño 1+2: -0.4 (-1.3 change).
Niño 3: -0.0 (-0.3 change).
Niño 3.4: +0.3 (-0.2 change).
Niño 4: +0.8 (-0.0 change).

[cycloneye]

Question for LarryWx. Do you agree with what CPC did to not announce in the may update that El NIño ended? I ask because you analize in a great way about this as you talk a lot about the RONI etc.

[StPeteMike]

Question for LarryWx. Do you agree with what CPC did to not announce in the may update that El NIño ended? I ask because you analize in a great way about this as you talk a lot about the RONI etc.

Interested as well, as I would assumed they would had went with neutral already or neutral in a week or so. Heck, I was bullish and thought they might have gone with very early stage of La Niña (just crossing the line from neutral) with the update.

[skyline385]

Question for LarryWx. Do you agree with what CPC did to not announce in the may update that El NIño ended? I ask because you analize in a great way about this as you talk a lot about the RONI etc.

Interested as well, as I would assumed they would had went with neutral already or neutral in a week or so. Heck, I was bullish and thought they might have gone with very early stage of La Niña (just crossing the line from neutral) with the update.

Its in their ENSO outlook posted some comments back, they use ONI for defining ENSO state which is a 3-month averaged index still sitting at 1.1ºC for FMA (Feb-Mar-Apr). From the ppt itself:

CPC considers El Niño or La Niña conditions to occur when the monthly Niño3.4 OISST departures meet or exceed +/- 0.5ºC along with consistent atmospheric features. These anomalies must also be forecasted to persist for 3 consecutive months.

Hence, they predicted ENSO Neutral by AMJ (85% chance) which would mean they would declare it in July and forecast La Nina by JJA (60% chance) corresponding to declaring it in September if their forecast verifies. BOM on the other hand doesn't use a lagging index like ONI and hence are quick to declare ENSO states.

[LarryWx]

Question for LarryWx. Do you agree with what CPC did to not announce in the may update that El NIño ended? I ask because you analize in a great way about this as you talk a lot about the RONI etc.

Interested as well, as I would assumed they would had went with neutral already or neutral in a week or so. Heck, I was bullish and thought they might have gone with very early stage of La Niña (just crossing the line from neutral) with the update.

Luis and Mike,
1. I feel like CPC has been inconsistent in the past. When I tried to predict when they were going to declare El Niño last year, I was wrong as they did it earlier than I expected.

2. Published: May 12, 2016

El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued by the Climate Prediction Center/NCEP/NWS

ENSO Alert System Status: El Niño Advisory/La Niña Watch
Synopsis: La Niña is favored to develop during the Northern Hemisphere summer 2016, with about a 75% chance of La Nina during the fall and winter 2016-17.

3. Published CPC ENSO Update

Published: May 9, 2024

El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued by the Climate Prediction Center/NCEP/NWS

ENSO Alert System Status: El Niño Advisory / La Niña Watch
Synopsis: A transition from El Niño to ENSO-neutral is likely in the next month. La Niña may develop in June-August (49% chance) or July-September (69% chance).

4. So, the wording of May of 2016 and the wording of May of 2024 update is fairly similar. They were both still in El Niño per ONI. MAM of 2016 ONI ended up at +0.9 and then it went neutral AMJ.
MAM of 2024 ONI is also looking to still be El Niño with ~+0.7, only slightly cooler than MAM of 2016. AMJ of 2024 should similar to AMJ of 2016 be neutral.

5. Even though RONI is found at a CPC ENSO site, it still has yet to be used for anything official. They’ve been sticking to ONI for official. However, unofficially FMA of 2024 was already down to neutral (+0.48) on a RONI basis and MAM RONI is likely going to already be close to 0.0.

[cycloneye]

Question for LarryWx. Do you agree with what CPC did to not announce in the may update that El NIño ended? I ask because you analize in a great way about this as you talk a lot about the RONI etc.

Interested as well, as I would assumed they would had went with neutral already or neutral in a week or so. Heck, I was bullish and thought they might have gone with very early stage of La Niña (just crossing the line from neutral) with the update.

Luis and Mike,
1. I feel like CPC has been inconsistent in the past. When I tried to predict when they were going to declare El Niño last year, I was wrong as they did it earlier than I expected.

2. Published: May 12, 2016

El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued by the Climate Prediction Center/NCEP/NWS

ENSO Alert System Status: El Niño Advisory/La Niña Watch
Synopsis: La Niña is favored to develop during the Northern Hemisphere summer 2016, with about a 75% chance of La Nina during the fall and winter 2016-17.

3. Published CPC ENSO Update

Published: May 9, 2024

El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued by the Climate Prediction Center/NCEP/NWS

ENSO Alert System Status: El Niño Advisory / La Niña Watch
Synopsis: A transition from El Niño to ENSO-neutral is likely in the next month. La Niña may develop in June-August (49% chance) or July-September (69% chance).

4. So, the wording of May of 2016 and the wording of May of 2024 update is fairly similar. They were both still in El Niño per ONI. MAM of 2016 ONI ended up at +0.9 and then it went neutral AMJ.
MAM of 2024 ONI is also looking to still be El Niño with ~+0.7, only slightly cooler than MAM of 2016. AMJ of 2024 should similar to AMJ of 2016 be neutral.

5. Even though RONI is found at a CPC ENSO site, it still has yet to be used for anything official. They’ve been sticking to ONI for official. However, unofficially FMA of 2024 was already down to neutral (+0.48) on a RONI basis and MAM RONI is likely going to already be close to 0.0.

Thanks as always for your clear explanation about this. I think the transition from Neutral to La Niña will be fast according to the CPC folks. They say El NIño ends in June and then say La NIña between June and August.

[weeniepatrol]

I personally don't agree with CPC; I agree with the BoM assessment that El Nino ended in April. I understand BoM has a higher threshold for El Nino and thus take longer than CPC to declare an event but also sooner than CPC to end it.

Per the ENSO blog it was splitting hairs either way, analogous to an analyzed 135-kt system with a couple 140-kt sfmrs.

The latest weekly measurement, which comes from the OISSTv2 dataset, was 0.5 °C above average. Given that the El Niño threshold is 0.5 °C, the team decided we’re right on the edge of the transition to neutral conditions.

This is my reasoning: look at this then look me in the eye and tell me this is El Nino I understand why CPC did it tho