El Ninos, and their counterpart La Ninas, have a history of causing substantial weather anomalies. La Nina is often linked, for example, to dryness in northern Argentina and southern US, but persistent rains in Australia. El Ninos, by contrast, tend to bring dryness to eastern Australia but increased winter rains in the US southern Plains, and wet and warm weather in parts of eastern South America.
Official meteorologists give their views on prospects for the El Nino-La Nina cycle.
Australian Bureau of Meteorology, December 5 2023
The long-range forecast for Australia indicates December-to-February rainfall is likely to be below median across much of northern and western Australia. Warmer days and nights are very likely for almost all of Australia.
El Niño continues in the tropical Pacific. Climate model forecasts indicate sea surface temperatures will remain above El Niño thresholds early into the second quarter of 2024.
The positive Indian Ocean Dipole (IOD) event continues. All international climate models surveyed by the Bureau suggest the positive IOD is likely to ease in December.
Australian Bureau of Meteorology, November 21 2023
El Niño continues in the tropical Pacific. Warmer than average sea surface temperatures (SSTs) persist in the tropical Pacific. The atmospheric indicators are also consistent with El Niño conditions.
The 2023 El Niño event is tracking around moderate strength with SSTs forecast to remain above El Niño thresholds into the early southern hemisphere autumn 2024.
The positive Indian Ocean Dipole (IOD) event continues and is currently tracking at strong levels. All international climate models surveyed by the bureau suggest the positive IOD is likely to ease in December, slightly later than usual.
Japan Meteorological Agency, November 10 2023
In October, the sea surface temperature (SST) for the NINO.3 region was above normal with a deviation of +2.2°C, which is the same value as August and September.
The five-month running mean value of the NINO.3 SST deviation for August was +1.9°C… In the atmosphere, convective activity over the central and eastern equatorial Pacific was above normal and easterly winds in the lower troposphere (ie trade winds) over the central equatorial Pacific were weaker than normal.
These oceanic and atmospheric conditions over the equatorial Pacific indicate that El Niño conditions have persisted. El Niño conditions have persisted in the equatorial Pacific since boreal spring this year.
JMA’s seasonal ensemble prediction system predicts that the subsurface water volume in the central and eastern parts will move eastward and the NINO.3 SST will be above normal during the prediction period. In conclusion, it is likely that El Niño conditions will continue through boreal spring next year (80%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| July-to-November | 0 | 0 | 100 |
| August-to-December | 0 | 0 | 100 |
| September-to-January | 0 | 0 | 100 |
| October-to-February | 0 | 0 | 100 |
| November-to-March | 0 | 10 | 90 |
| December-to-April | 0 | 10 | 90 |
| January-to-May | 0 | 20 | 80 |
| Data in percent | |||
US NOAA Climate Prediction Center, November 9 2023
Above-average sea surface temperatures (SST) across the equatorial Pacific Ocean were indicative of a strong El Niño, with anomalies increasing in the central and east-central Pacific in the past month.
Area-averaged subsurface temperatures anomalies increased slightly associated with the initiation of a downwelling oceanic Kelvin wave, which strengthened above-average subsurface temperatures in the central equatorial Pacific. Low-level wind anomalies were westerly in the east-central Pacific, while upper-level wind anomalies were easterly in the western and central Pacific…
Collectively, the coupled ocean-atmosphere system reflected a growing El Niño.
The most recent IRI plume favours El Niño to continue through the northern hemisphere spring. Based on latest forecasts, there is a greater than 55% chance of at least a “strong” El Niño persisting through January-March 2024. There is a 35% chance of this event becoming “historically strong” for the November-January season.
Stronger El Niño events increase the likelihood of El Niño-related climate anomalies, but do not necessarily equate to strong impacts.
In summary, El Niño is anticipated to continue through the Northern Hemisphere spring (with a 62% chance during April-June 2024).
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| October, November, December | 0 | 0 | 100 |
| November, December, January | 0 | 0 | 100 |
| December, January, February | 0 | 0 | 100 |
| January, February, March | 0 | 1 | 99 |
| February, March, April | 0 | 3 | 97 |
| March, April, May | 0 | 12 | 88 |
| April, May, June | 1 | 37 | 62 |
| May, June, July | 5 | 55 | 40 |
| June, July, August | 15 | 58 | 27 |
| Data in percent | |||
Australian Bureau of Meteorology, October 10 2023
Oceanic indicators firmly exhibit an El Niño state. Models indicate further warming of the central to eastern Pacific is likely.
Broadscale pressure and cloud patterns over the Pacific reflect El Niño. Trade wind strength over the past fortnight has been weaker than average in the western Pacific but is close to normal elsewhere.
Climate models indicate this El Niño is likely to persist until at least the end of February. El Niño typically leads to reduced spring and early summer rainfall for eastern Australia, and warmer days for the southern two-thirds of the country.
The positive Indian Ocean Dipole (IOD) continues to strengthen. The IOD index is +1.85 °C for the week ending 8 October. This is the sixth-highest weekly IOD index value since records for the Bureau SST dataset began in 2001.All models predict this positive IOD is likely to continue into at least December. A positive IOD typically leads to reduced spring rainfall for central and south-east Australia.
Australian Bureau of Meteorology, September 19 2023
An El Niño and a positive Indian Ocean Dipole are underway.
The declaration of these events, and their concurrence over spring, reinforces the bureau’s long-range rainfall and temperature forecasts, which continue to predict warmer and drier conditions for much of Australia over the next three months. The confirmation of an established El Niño increases the likelihood that the event will be sustained through the [southern hemisphere] summer period.
Oceanic indicators firmly exhibit an El Niño state. Central and eastern Pacific sea surface temperatures (SSTs) continue to exceed El Niño thresholds. Models indicate further warming of the central to eastern Pacific is likely.
Overall, there are signs that the atmosphere is responding to the pattern of SSTs in the tropical Pacific and coupling of the ocean and atmosphere has started to occur. This coupling is a characteristic of an El Niño event and is what strengthens and sustains an event for an extended period. Climate models indicate this El Niño is likely to persist until at least the end of February. El Niño typically leads to reduced spring and early summer rainfall for eastern Australia, and warmer days for the southern two-thirds of the country.
A positive Indian Ocean Dipole is underway. The Indian Ocean Dipole (IOD) index is +1.25 °C for week ending 17 September. This is its fifth week above the positive IOD threshold (+0.40 °C). The longevity of this trend, combined with the strength of the dipole being observed and forecast, indicate a positive IOD event is underway. All models predict this positive IOD will persist to at least the end of spring. A positive IOD typically leads to reduced spring rainfall for central and south-east Australia.
When a positive IOD and El Niño occur together, their drying effect is typically stronger and more widespread across Australia.
US NOAA Climate Prediction Center, September 14 2023
In August, sea surface temperatures (SSTs) were above average across the equatorial Pacific Ocean [Fig. 1], with strengthening in the central and east-central Pacific… Tropical atmospheric anomalies were also consistent with El Niño… Collectively, the coupled ocean-atmosphere system reflected El Niño.
The most recent IRI plume indicates El Niño will persist through the northern hemisphere winter 2023-24. Despite nearly the same ensemble mean amplitude as last month, the shorter forecast horizon means that the odds of at least a “strong” El Niño (≥1.5°C for the November-January seasonal average in Niño-3.4) have increased to 71%. However, a strong El Niño does not necessarily equate to strong impacts locally, with the odds of related climate anomalies often lower than the chances of El Niño itself (eg CPC’s seasonal outlooks).
In summary, El Niño is anticipated to continue through the northern hemisphere winter, with greater than 95% chance through January-March 2024.
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| August, September, October | 0 | 0 | 100 |
| September, October, November | 0 | 0 | 100 |
| October, November, December | 0 | 0 | 100 |
| November, December, January | 0 | 0 | 100 |
| December, January, February | 0 | 1 | 99 |
| January, February, March | 0 | 4 | 96 |
| February, March, April | 0 | 11 | 89 |
| March, April, May | 0 | 22 | 78 |
| April, May, June | 1 | 39 | 60 |
| Data in percent | |||
Japan Meteorological Agency, September 11 2023
In August, the sea surface temperature for the NINO.3 region was above normal with a deviation of +2.2°C, which is higher than in July.
The five-month running mean value of the NINO.3 SST deviation for June was +1.4°C… In the atmosphere, convective activity near the date line over the equatorial Pacific was slightly above normal and easterly winds in the lower troposphere (ie trade winds) over the central equatorial Pacific were weaker than normal.
These oceanic conditions are consistent with common features of past El Niño events and the atmospheric conditions indicate that common features of past El Niño events were becoming clear. El Niño conditions have persisted in the equatorial Pacific since boreal spring.
The warm subsurface water volume in the central and eastern part of equatorial Pacific (Fig.5) has maintained warm SST in NINO.3 region. JMA’s seasonal ensemble prediction system predicts that the subsurface water volume in the central and eastern part will migrate eastward and the NINO.3 SST will be above normal during the prediction period. In conclusion, it is likely that El Niño conditions will continue until boreal mid-winter (90%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| May-to-September | 0 | 0 | 100 |
| June-to-October | 0 | 0 | 100 |
| July-to-November | 0 | 0 | 100 |
| August-to-December | 0 | 0 | 100 |
| September-to-January | 0 | 0 | 100 |
| October-to-February | 0 | 0 | 100 |
| November-to-March | 0 | 10 | 90 |
| Data in percent | |||
Australian Bureau of Meteorology, August 15 2023
The bureau’s El Niño Alert continues, with El Niño development likely during spring. When El Niño “alert” criteria have been met in the past, an El Niño event has developed around 70% of the time.
The Indian Ocean Dipole (IOD) is currently neutral. Climate model forecasts suggest a positive IOD is likely to develop during spring. A positive IOD typically decreases winter-spring rainfall for much of Australia and can increase the drying influence of El Niño.
The Madden-Julian Oscillation (MJO) is in the western hemisphere and currently weak. Some climate models are forecasting a moderately strong MJO pulse over the Pacific Ocean in the coming week; this could assist development towards El Niño conditions.
The current status of the ENSO Outlook and other climate drivers does not change the long-range forecast of warmer and drier conditions across most of southern and eastern Australia from September to November.
Japan Meteorological Agency, August 10 2023
In July, the sea surface temperature (SST) for the NINO.3 region was above normal with a deviation of +1.8°C.
In the atmosphere, convective activity near the date line over the equatorial Pacific was above normal and easterly winds in the lower troposphere (ie, trade winds) over the central equatorial Pacific were near normal.
These oceanic conditions are consistent with common features of past El Niño events and the atmospheric conditions indicate that common features of past El Niño events were becoming clear. El Niño conditions have persisted in the equatorial Pacific since boreal spring.
JMA’s seasonal ensemble prediction system predicts that the subsurface water volume in the central and eastern part will be warmer and increase SSTs in the eastern part, and the NINO.3 SST will be above normal during the prediction period. In conclusion, it is likely that El Niño conditions will continue until boreal winter (90%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| April-to-August | 0 | 0 | 100 |
| May-to-September | 0 | 0 | 100 |
| June-to-October | 0 | 0 | 100 |
| July-to-November | 0 | 0 | 100 |
| August-to-December | 0 | 0 | 100 |
| September-to-January | 0 | 10 | 90 |
| October-to-February | 0 | 10 | 90 |
| Data in percent | |||
US NOAA Climate Prediction Center, August 10 2023
In July, El Niño continued as indicated by above-average sea surface temperatures (SSTs) across the equatorial Pacific Ocean.
Tropical atmospheric anomalies were also consistent with El Niño. Starting in mid-July, low-level winds were anomalously westerly over the western equatorial Pacific, while anomalous easterlies prevailed over the eastern Pacific.
Collectively, the coupled ocean-atmosphere system reflected El Niño.
The most recent IRI plume indicates El Niño will persist through the Northern Hemisphere winter 2023-24. Given recent developments, forecasters are more confident in a “strong” El Niño event, with roughly 2 in 3 odds of an event reaching or exceeding 1.5°C for the November-January seasonal average in Niño-3.4.
Note that a strong El Niño does not necessarily equate to strong El Niño impacts locally, with the odds of related climate anomalies often lower than the chances of El Niño itself.
In summary, El Niño is anticipated to continue through the northern hemisphere winter (with greater than 95% chance through December 2023 -February 2024).
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| July, August, September | 0 | 0 | 100 |
| August, September, October | 0 | 1 | 99 |
| September, October, November | 0 | 1 | 99 |
| October, November, December | 0 | 1 | 99 |
| November, December, January | 0 | 1 | 99 |
| December, January, February | 0 | 3 | 97 |
| January, February, March | 0 | 6 | 94 |
| February, March, April | 0 | 10 | 90 |
| March, April, May | 0 | 18 | 82 |
| Data in percent | |||
Australian Bureau of Meteorology, July 18 2023
The ENSO Outlook remains at El Niño “alert”. When El Niño Alert criteria have been met in the past, an El Niño event has developed around 70% of the time.
Central and eastern Pacific sea surface temperatures (SSTs) are exceeding El Niño thresholds. Models indicate further warming is likely, with SSTs remaining above El Niño thresholds until at least the end of the year.
The past month has seen the Southern Oscillation Index (SOI) shift back to neutral levels, with the 30-day SOI at +3.9 for the 30 days ending 16 July. The 90-day SOI is outside El Niño thresholds at -5.2. Sustained changes in wind, cloud and broad-scale pressure patterns towards El Niño-like patterns have not yet been observed.
This means the Pacific Ocean and atmosphere have yet to become fully coupled, as occurs during El Niño events.
US NOAA Climate Prediction Center, July 13 2023
In June, a weak El Niño was associated with above-average sea surface temperatures (SSTs) across the equatorial Pacific Ocean.
In contrast, the tropical atmospheric anomalies were weaker compared to the oceanic anomalies. For the June monthly average, low-level winds were near average over most of the equatorial Pacific.
Collectively, the coupled ocean-atmosphere system reflected a weak El Niño.
The most recent IRI plume indicates El Niño will persist through the northern hemisphere winter 2023-24. Forecasters favour continued growth of El Niño through the fall, peaking this winter with moderate-to-strong intensity. An event that becomes “historically strong” (seasonally averaged Niño-3.4 ≥ 2.0°C), rivalling the winters of 1997-98 or 2015-16, has an approximately 1 in 5 chance.
In summary, there is a greater than 90% chance that El Niño will continue through the northern hemisphere winter.
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| June, July, August | 0 | 3 | 97 |
| July, August, September | 0 | 4 | 96 |
| August, September, October | 0 | 4 | 96 |
| September, October, November | 0 | 4 | 96 |
| October, November, December | 0 | 4 | 96 |
| November, December, January | 0 | 4 | 96 |
| December, January, February | 0 | 7 | 93 |
| January, February, March | 0 | 10 | 90 |
| February, March, April | 0 | 15 | 85 |
| Data in percent | |||
Japan Meteorological Agency, July 10 2023
In June, the sea surface temperature (SST) for the NINO.3 region was above normal with a deviation of +1.3°C.
The five-month running mean value of the NINO.3 SST deviation for April was +0.7°C. SSTs and subsurface temperatures were above normal in almost all areas in the equatorial Pacific. In the atmosphere, convective activity near the date line over the equatorial Pacific was above normal and easterly winds in the lower troposphere over the central equatorial Pacific were near normal.
These oceanic and atmospheric conditions indicate that common features of past El Niño events were becoming clear. El Niño conditions are considered to have persisted in the equatorial Pacific since boreal spring.
The warm subsurface water volume in the central and eastern part of equatorial Pacific has maintained warm SST in NINO.3 region. JMA’s seasonal ensemble prediction system predicts that the subsurface water volume will be warmer and increase SSTs in the eastern part, and the NINO.3 SST will be above normal during the prediction period.
In conclusion, it is likely that El Niño conditions will continue until boreal autumn (90%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| March-to-July | 0 | 0 | 100 |
| April-to-August | 0 | 0 | 100 |
| May-to-September | 0 | 0 | 100 |
| June-to-October | 0 | 0 | 100 |
| July-to-November | 0 | 10 | 90 |
| August-to-December | 0 | 10 | 90 |
| September-to-January | 0 | 10 | 90 |
| Data in percent | |||
World Meteorological Organization, July 4 2023
The tropical Pacific is currently experiencing El Niño conditions as a result of rapid and substantial changes in oceanic conditions observed in recent months.
According to the latest predictions from the WMO Global Producing Centres of Long-Range Forecasts, there is a 90% probability of the El Niño during the second half of 2023 with only a 10% chance of weakening to an ENSO-neutral state. The likelihood of La Niña development is negligible.
Australian Bureau of Meteorology, July 4 2023
The ENSO Outlook remains at El Niño “alert”. When El Niño alert criteria have been met in the past, an El Niño event has developed around 70% of the time.
Central and eastern Pacific sea surface temperatures (SSTs) are exceeding El Niño thresholds. Models indicate a high likelihood of further warming, with SSTs exceeding El Niño thresholds until at least the beginning of the southern hemisphere summer.
In terms of atmospheric indicators, recent values of the Southern Oscillation Index (SOI) have risen back to neutral levels, with the 30-day SOI at +1.1 for the 30 days ending 2 July. The 90-day SOI remains close to, but just shy of, El Niño levels. Sustained changes in wind, cloud and broad-scale pressure patterns towards El Niño-like patterns have not yet been observed.
This means the Pacific Ocean and atmosphere have yet to become fully coupled, as occurs during El Niño events.
Japan Meteorological Agency, June 9 2023
In May 2023, the sea surface temperature (SST) for the NINO.3 region was above normal with a deviation of +1.1°C. The five-month running mean value of the NINO.3 SST deviation for March was +0.3°C. SSTs and subsurface temperatures were above normal in almost all areas in the equatorial Pacific.
In the atmosphere, convective activity near the dateline, which had been inactive through April, changed to be near normal and easterly winds in the lower troposphere (ie trade winds) over the central equatorial Pacific weakened to near normal.
These patterns in the ocean and atmosphere indicate El Niño conditions are present.
The warm subsurface water volume in the central and eastern part of equatorial Pacific has maintained warm SST in NINO.3 region. JMA’s seasonal ensemble prediction system predicts that the subsurface water volume will be warmer and increase SSTs in the eastern part, and the NINO.3 SST will be above normal during the prediction period.
In conclusion, it is likely that El Niño conditions will continue until boreal autumn (90%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| February-to-June | 0 | 100 | 0 |
| March-to-July | 0 | 100 | 0 |
| April-to-August | 0 | 100 | 0 |
| May-to-September | 0 | 100 | 0 |
| June-to-October | 0 | 10 | 90 |
| July-to-November | 0 | 10 | 90 |
| August-to-December | 0 | 10 | 90 |
| Data in percent | |||
US NOAA Climate Prediction Center, June 8 2023
In May, weak El Niño conditions emerged as above-average sea surface temperatures strengthened across the equatorial Pacific Ocean. All of the latest weekly Niño indices were more than +0.5°C… Collectively, the coupled ocean-atmosphere system reflected the emergence of El Niño conditions.
The most recent IRI plume indicates the continuation of El Niño through the northern hemisphere winter 2023-24. Confidence in the occurrence of El Niño increases into the fall, reflecting the expectation that seasonally averaged Niño-3.4 index values will continue to increase… At its peak, the chance of a strong El Niño is nearly the same as it was last month (56% chance of November-January Niño-3.4 ≥ 1.5°C), with an 84% chance of exceeding moderate strength.
In summary, El Niño conditions are present and are expected to gradually strengthen into the northern hemisphere winter 2023-24.
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| May, June, July | 0 | 14 | 86 |
| June, July, August | 0 | 7 | 93 |
| July, August, September | 0 | 6 | 94 |
| August, September, October | 0 | 5 | 95 |
| September, October, November | 0 | 4 | 96 |
| October, November, December | 0 | 4 | 96 |
| November, December, January | 0 | 4 | 96 |
| December, January, February | 0 | 4 | 96 |
| January, February, March | 0 | 7 | 93 |
| Data in percent | |||
Australian Bureau of Meteorology, June 6 2023
The bureau’s Enso outlook has been shifted to El Niño “alert”, indicating a 70% chance of El Niño forming this year.
This equates to roughly three times the normal chance of an El Niño forming. Central and eastern Pacific sea surface temperatures (SSTs) have warmed to El Niño thresholds. All models surveyed by the bureau are forecasting the likelihood of further warming and that these SSTs will remain above El Niño thresholds at least into the southern hemisphere spring.
Some atmospheric indicators such as the Southern Oscillation Index (SOI) have shifted towards El Niño thresholds, but wind, cloud and broad-scale pressure patterns indicate the Pacific Ocean and atmosphere are yet to reinforce each other, as occurs during El Niño events.
Australian Bureau of Meteorology, May 23 2023
The Pacific Ocean is currently Enso-neutral (neither La Niña nor El Niño). While all international climate models indicate it is very likely that tropical Pacific Ocean temperatures will reach El Niño thresholds during the southern hemisphere winter, an atmospheric response is also required for an El Niño to be declared. Thus far, little shift has been observed in atmospheric Enso indicators with trade winds and cloudiness patterns in the Pacific remaining indicative of Enso-neutral conditions.
The Enso outlook remains at El Niño “watch”. This indicates there is an increased risk of an El Niño occurring this year, at least double the usual chance. El Niño typically suppresses rainfall in eastern Australia during the winter and spring months. The status of the Enso outlook does not change the bureau’s long-range forecast for drier and warmer conditions across much of Australia for winter. The bureau’s climate model takes into account all influences from the oceans and atmosphere when generating its long-range forecast.
The Indian Ocean Dipole (IOD) is currently neutral. All five models suggest that a positive IOD event could develop in winter. A positive IOD typically supresses winter and spring rainfall over much of Australia, and if it occurs with El Niño, it can exacerbate El Niño’s drying effect. Long-range forecasts of IOD made at this time of the year have generally had low accuracy and thus should be viewed with caution beyond June.
US NOAA Climate Prediction Center, May 11 2023
During April, above-average sea surface temperatures (SSTs) expanded slightly westward to the east-central equatorial Pacific Ocean… Low-level wind anomalies were westerly during mid-April before switching back to easterly by the end of the month. Upper-level wind anomalies were westerly across most of the Pacific Ocean.
While the warming near coastal South America remains striking, the basin-wide coupled ocean-atmosphere system remained consistent with Enso-neutral.
The most recent IRI plume also indicates El Niño is likely to form during the May-July season and persist into the winter. The combination of a forecasted third westerly wind event in mid-late May, and high levels of above-average oceanic heat content, means that a potentially significant El Niño is on the horizon.
While at least a weak El Niño is likely, the range of possibilities at the end of the year (November-January) include a 80% chance of at least a moderate El Niño (Niño-3.4 ≥ 1.0°C) to a ~55% chance of a strong El Niño (Niño-3.4 ≥ 1.5°C). It is still possible the tropical atmosphere does not couple with the ocean, and El Niño fails to materialize (5-10% chance).
In summary, a transition from Enso-neutral is expected in the next couple of months, with a greater than 90% chance of El Niño persisting into the northern hemisphere winter.
| Probabilistic La Nina-El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| April, May, June | 0 | 62 | 38 |
| May, June, July | 0 | 18 | 82 |
| June, July, August | 0 | 11 | 89 |
| July, August, September | 0 | 9 | 91 |
| August, September, October | 0 | 7 | 93 |
| September, October, November | 0 | 6 | 94 |
| October, November, December | 0 | 6 | 94 |
| November, December, January | 0 | 6 | 94 |
| December, January, February | 0 | 7 | 93 |
| Data in percent | |||
Australian Bureau of Meteorology, May 9 2023
The Pacific Ocean is currently Enso-neutral (neither La Niña nor El Niño), with anomalous warmth in both the east and west of the basin. While oceanic Enso indicators have continued to warm and are forecast to reach El Niño thresholds during winter, there has been little to no shift towards El Niño in atmospheric Enso indicators. As a result, the Enso Outlook remains at El Niño “watch”. This means there is approximately a 50% chance of El Niño developing in 2023.
International climate models suggest further warming of the central and eastern tropical Pacific Ocean is likely. From July, six of the seven models indicate El Niño thresholds for sea surface temperatures will be met or exceeded, with all models meeting thresholds by August. Long-range forecasts for Enso increase in accuracy as winter approaches. El Niño typically suppresses rainfall in eastern Australia during the winter and spring months.
The Indian Ocean Dipole (IOD) is currently neutral. All five models suggest that a positive IOD event may develop by June. A positive IOD typically supresses winter and spring rainfall over much of Australia, and if it occurs with El Niño, it can exacerbate the drying effect. Long-range forecasts of IOD made in autumn have lower accuracy than those made at other times of the year.
Japan Meteorological Agency, May 12 2023
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| January-to-May | 0 | 100 | 0 |
| February-to-June | 0 | 60 | 40 |
| March-to-July | 0 | 30 | 70 |
| April-to-August | 0 | 20 | 80 |
| May-to-September | 0 | 20 | 80 |
| June-to-October | 0 | 20 | 80 |
| Data in percent | |||
Amis, May 4 2023
An El Niño event might be just around the corner. There is a 62% chance of El Niño developing during May-June-July rising to 86% chance during October-November-December, according to the IRI/CPC forecast.
Positive Indian Ocean Dipole (IOD) conditions may also develop during June to September, according to the Australian Bureau of Meteorology. Positive IOD conditions can enhance El Niño-related drying influences in Australia and the Maritime Continent, and wetting influences during the East Africa short rains.
Japan Meteorological Agency, April 11 2023
In March, the sea surface temperature for the NINO.3 region was near normal with a deviation of +0.4°C. Equatorial Pacific SSTs [sea surface temperatures] were above normal in the western and eastern part. Subsurface temperatures were above normal in almost all areas in the equatorial Pacific. In the atmosphere, convective activity near the date line over the equatorial Pacific was below normal and easterly winds in the lower troposphere (ie, trade winds) over the central equatorial Pacific were near normal. These patterns in the ocean and atmosphere indicate that ENSO-neutral conditions persisted in March.
The warm subsurface water volume observed in the central part of equatorial Pacific is expected to migrate eastward and increase SSTs in the eastern parts, but there are large uncertainties on the degree to which this contributes to the NINO.3 SST. JMA’s seasonal ensemble prediction system predicts that the NINO.3 SST will rise to above normal in boreal [northern hemisphere] summer.
In conclusion, it is more likely that El Niño conditions will develop by boreal summer (60%) than ENSO-neutral conditions will persist (40%).
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| January-to-May | 0 | 100 | 0 |
| February-to-June | 0 | 70 | 30 |
| March-to-July | 0 | 60 | 40 |
| April-to-August | 0 | 40 | 60 |
| May-to-September | 0 | 40 | 60 |
| June-to-October | 0 | 40 | 60 |
| Data in percent | |||
Australian Bureau of Meteorology, April 11 2023
The El Niño-Southern Oscillation (Enso) is currently neutral (neither La Niña nor El Niño). Oceanic and atmospheric indicators for the tropical Pacific Ocean are at neutral ) levels. However, there are some signs El Niño may form later in the year. Therefore, the outlook is at El Niño “watch”. This means there is approximately a 50% chance of El Niño in 2023.
International climate models suggest neutral Enso conditions are most likely to persist through autumn. From July, all but one of the models indicate El Niño thresholds will be met or exceeded, with all models by August. Current Enso outlooks extending beyond autumn should be viewed with some caution as they typically have lower forecast accuracy than forecasts made during other times of the year.
US NOAA Climate Prediction Center, April 9 2023
During the last month, above-average sea surface temperatures became more prominent in the western and far eastern equatorial Pacific Ocean. The latest weekly Niño-3.4 index value was 0.0°C, but the Niño 1+2 index value was +2.7°C, indicating significant warming along the South American coast… While the warming near coastal South America was striking, the basin-wide coupled ocean-atmosphere system was consistent with Enso-neutral.
The most recent IRI plume favours a transition to El Niño, beginning June-August and persisting into the winter. While the lower accuracy of forecasts during the spring can result in surprises, the recent oceanic Kelvin wave plus recurring westerly wind anomalies are anticipated to further warm the tropical Pacific Ocean. The coastal warming in the eastern Pacific may foreshadow changes across the Pacific basin. Therefore, an El Niño Watch has been issued, and the range of possibilities toward the end of the year includes a strong El Niño (4 in 10 chance of Niño-3.4 ≥ 1.5°C) to no El Niño (1 in 10 chance).
In summary, ENSO-neutral conditions are expected to continue through the northern hemisphere spring, followed by a 62% chance of El Niño developing during May-July.
| Probabilistic La Nina–El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| March, April, May | 0 | 99 | 1 |
| April, May, June | 0 | 70 | 30 |
| May, June, July | 0 | 38 | 62 |
| June, July, August | 0 | 25 | 75 |
| July, August, September | 1 | 19 | 80 |
| August, September, October | 1 | 17 | 82 |
| September, October, November | 1 | 15 | 84 |
| October, November, December | 1 | 13 | 86 |
| November, December, January | 1 | 12 | 87 |
| Data in percent | |||
Amis, April 6 2023
The El Niño-Southern Oscillation is currently in a neutral state. Enso neutral conditions are expected through July.
El Niño conditions may develop during the latter half of 2023, with a 61% chance of El Niño during August-September-October, according to the IRI/CPC forecast.
While long-range forecasts made at this time of year can be unreliable, El Niño events can have widespread, global impacts.
Should El Niño materialise, average to above-average rains could occur in Central Asia, southern North America, south-eastern South America, southern Europe, eastern East Africa, southern and eastern China. Average to drier than average conditions could occur in Central America, the Caribbean, northern South America, Southern Africa, the Maritime Continent, and Australia.
Australian Bureau of Meteorology, March 14 2023
La Niña has ended in the tropical Pacific Ocean. The El Niño-Southern Oscillation (Enso) is now neutral (neither La Niña nor El Niño) with oceanic and atmospheric indicators having returned to neutral Enso levels.
International climate models suggest neutral Enso conditions are likely to persist through the southern autumn. However, there are some signs that El Niño could form later in the year. Hence the bureau has issued an El Niño “watch”. This means there is a 50% chance of an El Niño in 2023.
US NOAA Climate Prediction Center, March 9 2023
La Niña has ended and Enso-neutral conditions are expected to continue through the Northern Hemisphere spring and early summer 2023.
During February, below-average sea surface temperatures (SSTs) weakened and currently persist only in the central Pacific Ocean… The atmospheric circulation anomalies across the tropical Pacific are lagging the changes in the ocean. Low-level easterly wind anomalies continue over the central Pacific Ocean. Upper-level westerly wind anomalies were evident over most of the Pacific. Suppressed convection persisted over the central tropical Pacific, while enhanced convection was observed over Indonesia.
Collectively, the coupled ocean-atmosphere system was consistent with Enso-neutral.
The most recent IRI plume favors Enso-neutral to continue through the spring, with El Niño forming during summer 2023 and persisting through the fall. In contrast, the forecaster consensus favours Enso-neutral through summer 2023, with elevated chances of El Niño developing afterwards. The smaller chances of El Niño relative to the model predictions are primarily because Enso forecasts made during the spring are less accurate, and also the tropical Pacific atmosphere is still fairly consistent with a cool/La Niña-like state.
However, it is possible that strong warming near South America may portend a more rapid evolution toward El Niño and will be closely monitored.
| Probabilistic La Nina–El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| February, March, April | 4 | 96 | 0 |
| March, April, May | 2 | 96 | 2 |
| April, May, June | 2 | 83 | 15 |
| May, June, July | 2 | 62 | 36 |
| June, July, August | 3 | 49 | 48 |
| July, August, September | 4 | 40 | 56 |
| August, September, October | 4 | 35 | 61 |
| September, October, November | 5 | 33 | 62 |
| October, November, December | 6 | 31 | 63 |
| Data in percent | |||
Abares, March 7 2023
The climate outlook is for average to above average rainfall between March and May 2023 for most of the world’s major grain- and oilseed-producing regions (Figure 3.3). The transition to an El Niño event is expected to result in enhanced probabilities of above-normal precipitation for most of Brazil, north-eastern and north-western parts of the United States, and Pakistan.
Moderately enhanced probabilities of below-normal precipitation are forecast for northwest Mexico and the south-western US, Australia and southern Brazil.
… An assumed move from La Niña into El Niño or positive IOD conditions would see less rainfall in Australia, but is likely to increase rainfall in a number of major northern hemisphere producers, such as the United States and Canada, and South American countries such as Brazil and Argentina. This would see greater agricultural
production in these countries and an increase in global supply, particularly for crops.
At the same time, we would see lower production in Australia and lower world prices for commodities as the global supply increases.
Amis, March 2 2023
The El Niño-Southern Oscillation (ENSO) is currently in the La Niña phase.
A transition to a neutral ENSO state is likely, with a 94% chance of ENSO neutral conditions in March-April-May, according to the IRI/CPC. ENSO neutral conditions are expected through July, after which El Niño conditions may develop, with a 60% chance of El Niño in August-September-October. While long-range forecasts made at this time of year can be unreliable, El Niño events can have widespread, global impacts.
Seasonal forecasts indicate La Niña precipitation impacts may continue through the next several months. While a transition to ENSO-neutral is anticipated during this time, atmospheric responses to La Niña can linger.
For eastern East Africa, where multi-year drought continues to severely impact food security, yet another below-normal rainy season is likely, based on forecast La Niña-like sea surface temperature gradients during spring.
Australian Bureau of Meteorology, February 28 2023
La Niña has weakened in the tropical Pacific Ocean and is likely near its end. Ocean indicators of La Niña have returned to neutral levels, while atmospheric indicators that remain at La Niña levels have started to weaken.
All but one of the surveyed international climate models suggest sea surface temperatures in the tropical Pacific will remain neutral (neither El Niño nor La Niña) through [southern hemisphere] autumn. One model is neutral in March and April but touches on El Niño thresholds in May. ENSO outlooks extending beyond autumn should be viewed with caution as models typically have lower forecast accuracy at this time of year.
Japan Meteorological Agency, February 10
In January, the sea surface temperature (SST) for the NINO.3 region was near normal with a deviation of -0.4°C. The five-month running mean of the NINO.3 SST deviation (NINO.3 index) was -0.8°C in November 2022 and was -0.5°C or below for 15 consecutive months up to November.
Equatorial Pacific SSTs were above normal in the western part and below normal in the central to eastern parts. Subsurface temperatures were above normal in the western to central part.
In the atmosphere, convective activity near the date line over the equatorial Pacific was below normal and easterly winds in the lower troposphere (ie, trade winds) over the central equatorial Pacific were stronger than normal.
Overall, these patterns in the atmosphere and ocean are consistent with features commonly seen in past La Niña events, but SSTs in the central part of equatorial Pacific have been near normal. This indicate that La Niña event, which had persisted since boreal autumn 2021, is coming close to its end.
The warm subsurface water volume observed in the central to eastern part of equatorial Pacific is expected to migrate eastward and increase SSTs in the eastern parts. JMA’s seasonal ensemble prediction system predicts that the NINO.3 SST will be near normal until the end of boreal winter and above or near normal in boreal spring to summer.
In conclusion, La Niña event is likely to transition to ENSO-neutral conditions by the end of boreal winter (90%) and it is equally likely (50%) that El Niño conditions will develop, or ENSO-neutral conditions will persist until boreal summer.
| Probabilistic La Nina-El Nino forecast, JMA |
|||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| November-to-March | 50 | 50 | 0 |
| December-to-April | 10 | 90 | 0 |
| January-to-May | 0 | 90 | 10 |
| February-to-June | 0 | 80 | 20 |
| March-to-July | 0 | 70 | 30 |
| April-to-August | 0 | 50 | 50 |
| Data in percent | |||
US NOAA Climate Prediction Center, February 9 2023
Although a weak La Niña was still apparent during January, below-average sea surface temperatures (SSTs) continued to weaken further across the equatorial Pacific Ocean. The latest weekly Niño index values were mostly near -0.5°C… Overall, the coupled ocean-atmosphere system continued to reflect La Niña.
The most recent IRI plume predicts a transition from La Niña to ENSO-neutral in the next couple of months. The forecaster consensus is largely in agreement. ENSO-neutral is expected to prevail during the spring and early summer.
There are increasing chances of El Niño at longer forecast horizons, though uncertainty remains high because of the spring prediction barrier, which typically is associated with lower forecast accuracy. In summary, ENSO-neutral conditions are expected to begin within the next couple of months, and persist through the northern hemisphere spring and early summer.
| Probabilistic La Nina–El Nino forecast, CPC/IRI | |||
| Season | La Niña | Neutral | El Niño |
|---|---|---|---|
| January, February, March | 63 | 37 | 0 |
| February, March, April | 15 | 85 | 0 |
| March, April, May | 5 | 94 | 1 |
| April, May, June | 3 | 82 | 15 |
| May, June, July | 3 | 61 | 36 |
| June, July, August | 4 | 47 | 49 |
| July, August, September | 5 | 38 | 57 |
| August, September, October | 6 | 34 | 60 |
| September, October, November | 7 | 31 | 62 |
| Data in percent | |||
