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, 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 | |||
