I’m generally pretty measured in how I discuss climate data. The only time I was truly shocked was when global temperatures rose 0.5 °C in September 2023, the warmest September on record. The July runs from 667 ensemble members across 14 seasonal forecast models now point to this year’s El Niño as not just the strongest event since reliable records began, but potentially the strongest ever, with a multi‑model median peak of 3.6 °C in the Niño 3.4 region—roughly 0.8 °C above the 2015‑16 record of 2.75 °C. Even the low end of the 80 % middle range sits at 2.8 °C, and 91 % of members exceed the previous record. The forecast trajectory shows a faster development than the 1997‑98 event and a genuine La Niña‑to‑El Niño launch in January, unlike the 2015 onset. All 14 models’ medians land in the “super” El Niño range, with only one model (JAMSTEC’s SINTEX‑F) below the record. Even using the relative ONI index, 11 of 14 models give a record‑likeness probability of 77 %. The data suggest a more likely than not strongest El Niño ever observed.

The models have consistently warmed their outlook each run from March to July, a classic signature of a real intensifying event rather than noise. Observed SSTs already sit ~2 °C above the 30‑year climatology, a threshold for a very strong El Niño if sustained.

The spatial maps from 6 NMME, 7 C3S, and SINTEX‑F all show the classic east‑Pacific tongue, with CMCC an outlier at 5.3 °C. Even discounting it, the multi‑model median remains robust.

Overall, the forecast indicates a likely record‑breaking El Niño, both in magnitude and speed of onset.