Please be aware that a planned maintenance session on the Data Stores underlying infrastructure on Tuesday 19th May 2026, from 11:30 to 14:30 UTC next week will affect the normal operation of the Data Stores, e.g. with potential impact on request queues, running of applications, API downloads etc. Access to MARS-stored datasets (e.g ERA5, CERRA, Seasonal Forecast data, EFAS, CAMS global forecast, etc) is expected to be disrupted.
Should users encounter difficulties, we recommend in the first instance to please check the ECMWF Service Status page for the latest information available with respect to ongoing system sessions.
Please refrain from submitting requests as long as “Data Stores” is not showing in green (all clear) status on the ECMWF Status page.
We thank our users for their patience.
ECMWF Support