Advancing global NWP through international collaboration

High resolution mean sea level pressure and ensemble spread

Tuesday 18 December, 12 UTC T+96 Valid: Saturday 22 December, 12 UTC

Ensemble forecasts explained
One 'ensemble forecast' consists of 51 separate forecasts made by the same computer model, all activated from the same starting time. The starting conditions for each member of the ensemble are slightly different, and physical parameter values used also differ slightly. The differences between these ensemble members tend to grow as the forecasts progress, that is as the forecast lead time increases.

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SciArt Louise Arnal

A journey through science and art

Louise Arnal is a scientist with a lifelong love of art. Here she explores the relationship between art and science and talks about her involvement in a number of SciArt projects.

18 December 2018


News highlights of 2018

The year 2018 was rich in developments across ECMWF’s activities, including a major upgrade of the Integrated Forecasting System; the Annual Seminar on Earth system data assimilation; the launch of the Climate Data Store; and the release of an invitation to tender for ECMWF’s next high-performance computing facility.

17 December 2018

Three new ECMWF Fellowships awarded

ECMWF has appointed Louise Nuijens (TU Delft), Marc Bocquet (École des Ponts ParisTech) and Maria-Helena Ramos (Irstea) to three-year Fellowships from 1 January 2019.

10 December 2018

Newsletter cover images montage

Diverse project work in focus

Articles presenting ECMWF’s involvement in diverse areas, from our graduate training programme and support for national and international initiatives to information on publications such as our User Guide.

10 December 2018

Forecast charts and data

We provide current forecasts, climate reanalyses and specific datasets. These are available via the web, point-to-point dissemination, data servers and broadcasting.

2m temeprature errors twitter image

Highlighted tweet

An official ECMWF target is to reduce the frequency of errors >5°C in ensemble 2m temperature forecasts for 5 days ahead. Related verification charts like this are monitored daily. Squares/triangles show errors >5°C. Warm biases over Scandinavia are under investigation.


Forecasts, analyses, climate re-analyses, reforecasts and multi-model data are available from our archive (MARS) or via dedicated data servers or via point-to-point dissemination.

Accessing forecasts

Researchers, WMO members, commercial users and satellite data providers can gain access to ECMWF forecast products under one of our various license agreement types.

Advancing weather science

Education is a key element of our work at ECMWF, enabling our partners to get the most from ECMWF's services and develop an advanced understanding of forecasting.

ECMWF lecture theatre

ECMWF workshops are open to the worldwide meteorological community, though some training is restricted to member states.

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Serving meteorology

International collaboration is fundamental to the work of ECMWF, working with the EU and the meteorological community at large, including the World Meteorological Organization, space agencies, and scientists around the world.