On these pages you can find information about planned changes to the IFS forecasting system and documentation describing previous changes. Please note that for planned changes this information is subject to revisions as we proceed with experimentation.

Formal announcements of the implementation schedules for new model cycles will still be made by email, and relevant information will then be posted on dedicated pages on the ECMWF web site, where you can also find information about previous changes to the ECMWF forecasting system.  The terminology used is described in Terminology for IFS testing.

Planned changes

  • Implementation of IFS Cycle 49r1 - Scheduled for Q4 2024 (TBC)

Past changes

See also

Mailing list

A mailing list has been created to inform interested parties about IFS changes.

To subscribe or unsubscribe, please send an email to


with either subscribe or unsubscribe as Subject.