ECMWF Transitions to Open Data

Open-Meteo Now Distributes IFS HRES at 9 km

We are excited to share some great news for the weather and climate community! On October 1st, 2025, the European Centre for Medium-Range Weather Forecasts (ECMWF) officially transitioned to an open-data policy. This marks a major step forward in making world-class weather forecasts accessible to everyone.

As part of this transition, Open-Meteo is proud to redistribute the ECMWF Integrated Forecasting System (IFS) HRES forecasts at the full 9 km resolution — without any additional delay.

Previously, ECMWF’s open-data stream was limited to 0.25° (~28 km) grid spacing, fewer variables, reduced time resolution and an additional 2 hours delay. Making it less ideal for critical real-time weather forecasting. Now, users can access the highest-quality deterministic forecasts, updated every six hours, with native 9 km resolution for unparalleled global coverage.

This is a significant milestone for developers, researchers, and organizations who rely on accurate, high-resolution weather data. By combining open access with modern APIs, Open-Meteo makes it easier than ever to build reliable weather-powered applications and services.

You can access ECMWF IFS forecasts directly via the Open-Meteo API, with instant availability of time-series data at 1-hour resolution.

Comparing cloud cover forecasts from IFS HRES, IFS 0.25° and AIFS 0.25°

In addition, the full dataset is also provided through the AWS Open Data Sponsorship program on a public S3 bucket. The bucket offers multiple access options, including views optimized for long time-series data, individual model runs, and a traditional spatial distribution format for map generation with just 2-3 minutes delay.

Stay tuned — this is just the beginning of a new era in open weather data!