Nature, Published online: 21 October 2026; doi:10.1038/d41586-026-03077-0

An innovative artificial-intelligence application enhances weather forecasting in the difficult subseasonal range, providing accurate forecasts of precipitation, temperature and pressure 3–5 weeks in advance. The tool refines both physics- and AI-based weather models and improves the early prediction of extremes of heat, cold, rainfall and flooding.