The European Centre for Medium-Range Weather Forecasts (ECMWF) is an independent international organization supported by 23 European Member States and 11 Cooperating States. Headquarters are in Reading (United Kingdom) with offices in Bologna (Italy) and Bonn. The ECMWF site in Bonn opened in 2021 and hosts ECMWF's EU-related activities.

ECMWF is a world leader in global medium-range forecasting and projections. The centre has one of the largest supercomputer facilities and meteorological data archives in the world. Its findings are made available to the European national meteorological services.