Overview
- The World Meteorological Organization update published Thursday, May 28, 2026 raised the odds that 2026–2030 will be record or near‑record warm, with a 75% chance the five‑year mean exceeds 1.5°C, about an 86% chance that at least one year will be the hottest on record, a 91% chance of at least one year temporarily exceeding 1.5°C, and less than 1% chance of any single year exceeding 2°C.
- The report says a likely El Niño forming in late 2026 would amplify global temperatures and makes 2027 the year most at risk of becoming the hottest on record, a point emphasized by the bulletin’s lead author Leon Hermanson.
- Scientists producing the update combined model ensembles and observations from about 13 institutes to produce the probabilistic forecast and explicitly note that single‑year or five‑year exceedances differ from the multi‑decadal warming measured for Paris Agreement goals.
- The bulletin projects pronounced Arctic amplification, with coming northern winters about 2.8°C warmer than 1991–2020 normals and expected regional declines in sea‑ice concentration in the Barents, Bering and Okhotsk seas.
- Rising short‑term extremes and repeated warm years increase direct risks to health, food and water systems and infrastructure, and they will shape national preparedness and international policy discussions as the long‑term warming trend that made 2015–2025 the 11 warmest years continues.