+1.5°C anomaly in the Niño-3.4 region is NOAA's CPC threshold for a "strong" El Niño event, with a 62% probability of occurrence in June–August 2026 (Noll, 2026).
(Noll, 2026)
Noll, B. (2026, abril 6). Super El Niño chances increasing risks. The Washington Post. https://www.washingtonpost.com/weather/2026/04/06/super-el-nino-chances-increasing-risks/