Dear colleague,
Welcome to the August edition (Nr. 5) of the Data Support News!
As ever, we're pleased to share recent developments to help you stay ahead of key changes. A copy of each update is also shared in the ECMWF Forum and as a newsletter in our Data & Charts blog for future reference.
ECMWF Data Support team at EMS 2025
Many ECMWF colleagues will be attending EMS 2025 in Ljubljana, Slovenia, and we'd like to offer the opportunity for users to meet our Data Support colleague. For those attending, please feel free to raise a support ticket to arrange a meeting with our colleague and to hear more about our Open Data transition, please stop by the Open Data session on Tuesday 9th September between 14:00 - 16:00 CEST.
ECMWF User Event - UEF 2025: Follow along live!
ECMWF's annual user event, Using ECMWF's Forecasts (UEF), is rapidly approaching, and we'd like to invite all users to watch online for the latest ECMWF updates and information. All talks will be livestreamed throughout. The event starts on Monday 15th September with presentations from Director-General Florence Rabier, Deputy Director-General Florian Pappenberger and Director of Computing, Martin Palkovic. Find out more about ECMWF's strategy and future, then attend in-depth sessions on the past, present and future of ECMWF. Topics will cover Machine Learning, Open Data, the upcoming ERA6 reanalysis dataset and more!
More information on the programme can be found here and feel free to reach out to Data Support Team if you have questions.
GRIB2 Migration - Dataset availability
As part of the Migration to GRIB edition 2 (MTG2), ECMWF is gradually moving all operational data from GRIB1 to GRIB2 format. GRIB2 provides more flexibility for encoding and describing meteorological data and will allow ECMWF to continue expanding its range of products.
Sample datasets are already available for testing and evaluation. Users are encouraged to download and familiarise themselves with the new format ahead of the full migration. More details, including access instructions, can be found on the Migration to GRIB edition 2 Information page.
We recommend that users begin testing GRIB2 sample data and adapting their tools and processes, as GRIB1 data will be phased out in 2026.
Open Data Transition - Update
We're now 1 month away from the big moment! The ECMWF Product Requirements Catalogue (PRC) has been updated so that if you're ordering data after 01 October 2025, the Information Cost will automatically be removed. If you're ordering data between 01 July 2025 and 01 October 2025, the quote will be adjusted to calculate only the Information Cost for the period that it applies. Of course, if you wish to see the cost before Open Data, you can use an older version of ecQuote in the PRC when viewing the order.
So what happens on 01 October 2025?
From 00:00 on 01 October 2025, the current restrictions around redistribution will be abolished for all Products in the ECMWF Real-time Catalogue! Otherwise, very little changes in terms of technical delivery.
The current IFS Open Dataset will continue in its current configuration with 1h latency and may be adjusted later in 2025 to include higher-resolution products.
This means you will be able to redistribute ECMWF unmodified products, including brokering, selling, etc.
Some key reminders:
- The products will be under the CC-BY-4 licence, which requires a clear attribution when using and sharing the Products.
- If you redistribute, broker, or otherwise sell ECMWF Products, you will be responsible for the support of users accessing data via your services.
New filenaming convention
As many of you will be aware, with the implementation of AIFS-Single and AIFS-ENS (CRPS), ECMWF introduced a new naming convention and will gradually phase out the current filenaming convention. The current 'Legacy' naming convention is now reaching its limit as we expand our products, and after user feedback we feel this new naming convention will be more intuitive.
ECMWF is happy to share that the new naming convention will be optional for IFS and AIFS products soon. Users with access to the Product Requirements Editor (PREd) will be able to make these changes themselves by selecting a naming convention per feed.
Some key information:
- The default naming convention when requesting IFS products will be the 'legacy' (current) naming scheme
- Users can select one of two new naming conventions: 'ECMWF' or 'WMO'
- The old naming convention will be removed with the GRIB2 migration in 2026
We encourage users to start testing and evaluating the naming convention at their earliest convenience, and your feedback is very important to us!
If you have questions or issues, please raise a ticket in the ECMWF Support Portal and mark it as 'Filenaming feedback for Data Support' - this will help us to expedite your request.
As always, we're here to support your data operations and provide clarity around changes that may affect your setup. Should you have any questions, don't hesitate to reach out via the ECMWF Support Portal.
Best regards,
ECMWF Data Support Team