ECMWF S2S real-time forecast and the corresponding reforecast data

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1

We found that the ECMWF S2S real-time forecast and the corresponding reforecast data for the 20260723 issue do not appear to be available from ECDS yet. We have checked the ECDS/S2S pages and ECMWF Forum announcements, but could not find a specific notice explaining this delay.

Could you please let us know whether there is any known issue or expected delay for the ECMWF S2S 20260723 data release?

2

(I’m not from ECMWF) Some services like MARS was down yesterday and so 20260722 wasn’t available either. It’s all green now: https://status.ecmwf.int/

I’d check back for 20260724 tomorrow to see if that’s available if you don’t get an official reply.

3

Still no new forecasts (usually the latest run is released by now).

4

+1. 2026-07-22 and 2026-07-23 are not available. Per the contest guidelines we are not supposed to use later than 2026-07-23.

5

Our download script failed as well, saying that the forecast S2S ECMWF 2023-07-23 is not yet available.

6

Good morning all,

Please accept our apologies. ECMWF sub-seasonal forecast data with a forecast initialisation date later than 2026-07-21 has not been transferred to the ECMWF Data Store. We have contacted the relevant internal team.

We will of course accept email submission for this week’s forecast and will keep you all posted on this forum post.

Sorry once again,

Josh

7

Thank you for your prompt and transparent response – we really appreciate it. we understand these things happen.

While we will keep an eye on the forum post for further updates, we were wondering if you might have a rough estimate of when the data transfer issue might be resolved. This would help us plan our workflow accordingly.

Thanks again for your help, and we look forward to your updates.

8

Hi @yu_bing ,

As soon as I have more information, I will pass it on.

Josh

9

Dear Josh,

Noted with thanks. We will wait for your further updates.

Best regards,
Yubing

10

Hello everyone,

I’ve gotten feedback that the forecasts are now available.

All the best
Rebecca

11

Dear all,

You beat me to it @Rebecca_Wiegels !

ECMWF S2S forecasts with a 48-hour latency are now available on ECDS.

Sorry for the inconvenience caused.

Email submission will be accepted to those affected by the data outage.

An example of email submission is explained at: Potential for failed submission between 19th to 22nd March

Thanks all,

Josh