Overview
- National multisectoral assessment ENFEN raised the probability of an 'extraordinary' coastal El Niño in a Sept. 14 report and said the event could run from September 2026 through January 2027 and possibly persist into later 2027.
- Senamhi measurements show sea-surface temperature anomalies of about 3.5°C off Peru’s coast, a magnitude officials say is driving unusually warm conditions now and feeding forecasts of stronger impacts.
- Senamhi has issued high-level heat alerts and reports that spring weather already feels like summer in Lima, with daytime highs above 30°C expected through spring and projected land temperatures up to 36°C in summer 2027.
- Forecasters warn the northern coastal strip and vulnerable river basins will face concentrated heavy rainfall and higher river flows mainly in the first trimester of 2027, raising flood and runoff risks in places such as the Rímac basin (Chaclacayo and Chosica).
- Authorities emphasize continued monitoring and preparedness for heat-health measures, possible changes to school calendars and infrastructure stress, and note that the exact timing and local intensity of heat or heavy rain remain uncertain.