Analysis runs for the four main synoptic hours 00, 06, 12 and 18 UTC; forecast runs out to 10 days based on the 00/12 UTC analysis forecast.
Data is produced at the surface, on model levels, pressure levels, isentropic levels and levels of equal potential vorticity.
ECMWF's deterministic atmospheric model is coupled with a wave model allowing two-way interaction between wind and waves.
Analyses are available for the four main synoptic hours 00, 06, 12 and 18 UTC; forecasts are produced globally out to 10 days based on the 00/12 UTC analysis.
European wave model
ECMWF runs the wave model at a finer resolution for a limited area. It used to be called the Mediterranean model but is now known as the European wave model.
Analyses are available for the four main synoptic hours 00, 06, 12 and 18 UTC; forecasts are produced out to 5 days based on the 00/12 UTC analysis.
Ensemble Prediction System and monthly forecast
The Ensemble Prediction System (EPS) runs 50 different perturbed forecasts with perturbed initial conditions and a control (unperturbed) forecast with a forecast range of 15 days.
The monthly forecast system is linked to the EPS; it extends the forecast range from day 16 to day 46.
The hindcast system consists of a 10-member ensemble of 46-day EPS/monthly integrations, starting on the same day and month as the real-time forecast for each of the past 18 years.
System 5 seasonal forecast
The seasonal forecast system couples three models: the atmospheric, wave and ocean models.
The seasonal forecasts consist of a 51-member ensemble. SEAS5 uses the community ocean model NEMO (Nucleus for European Modelling of the Ocean), but with an upgraded model version, ocean physics and resolution. The forecasts run for seven months, based on the 00 UTC analysis.
Once per quarter (Feb, May, Aug, Nov), a 15-member ensemble is run for a further 6-months producing a 13-month forecast.
A set of re-forecasts (otherwise known as hindcasts or back integrations) are made starting on the 1st of every month for the years 1981-2016. They are identical to the real-time forecasts in every way, except that the ensemble is only 25 rather than 51.
Synoptic monthly means
ECMWF maintains an archive of monthly mean data from the atmospheric and wave model.
The resolution and internal representation of the archive may change according to changes in ECMWF's operational practice.