ECMWF will update the default versions of its software packages and libraries used on Atos HPCF, AG and ECS as part of the regular update cycle.
When?
The changes will take place on Wednesday 17 June 2025 09:00 UTC
Do I need to do anything?
We strongly recommend you test that your programs, scripts and suites work with the new versions of any software or library affected before the change happens.
Table of contents
Highlights
Python 3.13 becomes default, with Earthkit 1.0
For our Python users, we now offer a more recent version of Python 3.13 with the usual extra modules found on the previous default 3.12. It features new versions of many extras, like NumPy version 2 and the latest earthkit 1.0 stack. While the final 1.0 release is finalised, the version featured is the latest release candidate. It will be updated to final 1.0 once it is out.
Note that new versions of other packages with python bindings may only come with support for the new Python 3.13.
You can check all the extra packages included in this installation with:
module help python3/jun26
ECMWF software improvements
There have been a number of improvements and changes in our ECMWF software and libraries since our last default change in November 2025. The new versions fully support the latest operational IFS cycles and also pave the way for the upcoming Migration to GRIB2. See the blog posts for all the software releases since then to learn about what is new in ecCodes, Magics or Metview.
A lot of other bugfixes and improvements
All the new versions, both ECMWF and 3rd Party, come with a number of bug fixes and improvements. You may see the change logs and news for any individual package or library in the list below if you want to have all the details.
How to use the new versions for testing BEFORE the update
Users are strongly encouraged to test their software applications and data processing chain with the new versions of the various software packages before the date of the change to the default versions.
The new versions of the software packages can be selected by using the jun26 tag in modules. For example:
|
How to revert to the old versions in case of problems AFTER the update
Users that experience problems with the new default software packages after the update will be able to revert to the old default versions. These can be selected with the commands:
|
Please let ECMWF know if you need to revert to the old version of any of the packages after the update of the defaults has taken place.
Change list
ECMWF Software
The new version of the ECMWF Toolbox (ecmwf-toolbox module) is 2026.04.0.0, replacing 2025.10.1.0. This table summarises the changes in the version of the different packages within the bundle:
| Package | Default version | Release notes | Download page | |
|---|---|---|---|---|
| Before | After | |||
| CodesUI | 1.8.1 | 1.8.1 | CodesUI - Change History | CodesUI - Releases |
| ecCodes | 2.44.0 | 2.47.0 | ecCodes Releases | |
| Magics | 4.16.0 | 4.16.1 | Latest News | Magics Releases |
| Metview | 5.26.1 | 5.26.4 | Metview Releases | |
| ODC | 1.6.0 | 1.6.3 | README | ODC Releases |
Besides ecmwf-toolbox, the following ECMWF packages with their corresponding module also see their default changed:
| ecFlow | 5.13.4 | 5.16.0 | ecFlow Releases |
|---|
ecFlow Servers update
General purpose ecFlow servers and those running Time-Critical Option 2 workloads will also be updated to run version 5.16.0.
Please see the Release notes for full details of the changes implemented in each package.
Third-party software
Some of the versions in this list may already be the default for a specific package, so no changes will be made in those cases.
Potential issues
ecFlow and python3 incompatibilities
If in your ecFlow tasks you use the ecFlow Python bindings, they may not work if using mixing older and newer versions of ecFlow and Python.