Overview
- Official agencies confirmed late August that El Niño is active in the equatorial Pacific and multiple international and regional models assign very high odds the episode will strengthen to a very strong peak in October–December 2026.
- For Argentina the forecast increases the chance of above‑normal spring and early‑summer rainfall, with the AMBA, Litoral and Pampeana cited as higher‑risk areas for storms, urban flooding and river rises.
- Provincial authorities in Santa Fe have already moved to emergency water‑management measures, accelerated hydraulic works and launched public preparedness campaigns to reduce the risk of an excess‑water event.
- Mexican institutions led by UNAM warn of regionally uneven impacts that include exceptional heat waves and drought risk in central, southern and Yucatán areas together with possible wetter spells in the northwest and heightened hurricane risk.
- Scientists emphasize uncertainty and a probabilistic outlook: key signals to watch are Niño 3.4 sea‑surface anomalies, subsurface Kelvin waves and ocean–atmosphere coupling, and those indicators will determine local timing and the scale of impacts on agriculture, health and river basins.