Integrated Forecasting System

All our forecasts are produced with the ECMWF Integrated Forecasting System (IFS). It includes a sophisticated data assimilation system and global numerical model of the Earth system, as well as supporting infrastructure to make forecast products available to our Member and Co-operating States and other users.  

The data assimilation system combines the latest weather observations with a recent forecast to obtain the best possible estimate of the current state of the Earth system – known as an analysis.

The Earth system model has a model of the atmosphere at its heart, coupled to models of other Earth system components, such as the ocean.

Starting from the analysis, our Earth system model is then used to forecast the likely evolution of the weather and some other aspects of the Earth system.

Evolution of the IFS

The IFS undergoes regular updates in order to improve our forecasts. Our collaborative research activities keep ECMWF at the forefront of developments in numerical weather prediction and such developments feed through into improvements in our operational forecasts.

IFS upgrades are listed below with their identifier (Cycle 47r3 for example).

IFS cycle

Implementation date

News item

Cycle 48r1 27 Jun 2023

Model upgrade increases skill and unifies medium-range resolutions

Cycle 47r3 12 Oct 2021

Forecast upgrade improves moist physics and use of satellite observations.

Cycle 47r2 11 May 2021

Forecast upgrade innovates on single precision and ensemble resolution. 

See older IFS cycles