Overview
- Daily sea-surface temperature anomalies in the Niño 3.4 region reached about +3.07°C in mid‑September, a value that ties or slightly exceeds the 2015 daily record on the common 1991–2020 Oceanic Niño Index.
- Measurements differ by method: NOAA’s newer Relative Oceanic Nino Index (RONI) adjusts for broad tropical warming and currently shows lower values, leaving the event below the RONI all‑time record.
- Seasonal forecast ensembles from NOAA CPC, Copernicus C3S, ECCC and JAMSTEC overwhelmingly project further strengthening with many runs peaking between November and January and a model-cluster peak range around 3.4–4.6°C.
- The El Niño is already producing real effects, including drought-driven crop and livestock losses in parts of Central America, reduced Panama Canal traffic from low reservoir levels, and drought-linked wildfires in Indonesia.
- Scientists and the WMO warn the event is likely to persist into early 2027, with most of its influence on global atmospheric temperatures and wider weather impacts expected to appear with a several‑month lag.