For the first time, a satellite orbiting Earth is beaming cloud radar data directly into the world's most advanced weather forecasting system. The European Centre for Medium-Range Weather Forecasts, or ECMWF, began assimilating these observations on 10 June 2026, marking a historic leap in how meteorologists see the sky.
A radar that sees through clouds
The EarthCARE satellite, launched in May 2024, carries a cloud profiling radar provided by the Japan Aerospace Exploration Agency (JAXA). Unlike conventional weather satellites that only capture cloud tops, this radar penetrates through clouds to reveal their internal structure. It measures where clouds form, how they dissipate, the size and distribution of particles, their fall velocity, and how much water they hold. This level of detail was previously unavailable from space.
From climate science to daily forecasts
EarthCARE was designed primarily for climate research. Its four instruments work together to untangle how clouds and aerosols heat or cool the atmosphere, a relationship that remains one of the biggest uncertainties in climate projections. But the same observations turned out to be directly useful for weather forecasting. Clouds are a notorious challenge for forecast models. By feeding real radar measurements into ECMWF's Integrated Forecasting System, forecasters now start with a more accurate picture of current atmospheric conditions. This improves predictions of what happens next.
Why this matters for people on the ground
Better cloud data means better forecasts of rain, snow, and storms. For the European public and communities worldwide that rely on ECMWF forecasts, this translates into more reliable warnings and daily outlooks. The achievement is also a practical payoff from a research mission. EarthCARE is a joint venture between the European Space Agency and JAXA, and its cloud profiling radar is the first spaceborne instrument of its kind to be used operationally in a global forecasting system. The data now flows into the same models that guide airlines, farmers, emergency services, and millions of people checking the weather on their phones.
A new benchmark for satellite meteorology
This operational assimilation proves that a research satellite can deliver immediate, tangible benefits while still pursuing its long-term scientific goals. EarthCARE continues its mission to reduce uncertainty in climate science, but its cloud radar has already changed how weather forecasts are made. For the first time, forecasters have a space-based tool that sees inside clouds, not just their surface. That shift will only sharpen predictions in the years ahead.
