25/March/2020

• An error in the retrieval of high-frequency data (daily/subdaily) from NCEP seasonal forecast data (NCEP CFSv2) data has been detected. This has been documented as "known issue" E7 (C3S Seasonal Forecast known issues)
  

  It affects all data available in the high-frequency (daily/subdaily) datasets:

  • Seasonal forecast daily data on single levels (seasonal-original-single-levels)

  • Seasonal forecast daily data on pressure levels (seasonal-original-pressure-levels)

  Members with start time at 06h,12h and 18h are not being retrieved from the archive by the CDS and just members with start time at 00h are returned.

11/February/2020

• An error in the processing of surface solar radiation variables for NCEP has been reported (Known issue E6 in the "not fixed issues" section here)
  • The parameters "surface net solar radiation" and "surface solar radiation downwards" (and their counterparts in the monthly statistics and anomalies datasets) have been accidentally swapped with each other in the case of
    
    • Forecasts with nominal start dates from October 2019 to February 2020 (both included)
    • Hindcasts with nominal start dates October, November, December, January and February
  • A fix has been already introduced in the operational production of C3S data; starting from nominal start date March 2020 real-time forecast data (and its corresponding hindcasts) will not be affected by this.
  • A recovery process for the affected data already published will be put in place. Details about when this will become available will be announced here.

8/January/2020

• The recovery process for missing monthly and anomalies data for NCEP contribution has been now finished. More details in known issues E4.a1 and E4.a2 ("fixed issues" section here).

13/December/2019

• With the release of December 2019 C3S seasonal forecasts a new encoding for monthly data has been implemented allowing users to get the real initialization date of each individual ensemble member from lagged start forecasting systems.
  More information here.
  Related information about known issues here (items E4.a1 and E4.a2)

2/December/2019

• A data issue has been recently reported affecting CMCC contribution data for start dates between March and September. The impact of those errors is quite limited in general, but it can be noticeable for "geopotential height" variable in pressure levels.
  More details can be found in known issues E5a and E5b here.

29/November/2019

• The recovery process for wrong snowfall data from CMCC contribution has been now finished. More details in known issues E3a, E3b, E3c and E3d ("fixed issues" section here)

7/November/2019

• The recovery process for the wrong snowfall data from CMCC contribution has started for the November start date hindcasts (i.e. 1993 to 2016). More details can be found in known issues E3.a ("not fixed errors" section here)

11/October/2019

• All the relevant documentation for the new forecasting systems to be released with October 2019 real-time forecasts (Météo-France System7 and NCEP CFSv2) is now available.
• Due to technical reasons, the publication of monthly mean data for NCEP has been delayed, but the full set of high-frequency data will be available as expected in the CDS. This has been recorded as known issue E4 (see details here in the "not fixed errors" section)
  
  • As a side effect, publication of updated MetOffice hindcasts for November nominal start date (system=14) is also delayed.
  • The current estimate is that all the above-mentioned delayed data would be made available on the week commencing on 4th November.

22/August/2019

• An upgrade to Météo-France contribution (change of operational forecasting system from System 6 to System 7) will be introduced from October 2019 nominal start date. Documentation for the new system here.
• A new data stream will be added to the C3S seasonal forecast multi-system in October 2019. This data comes from NCEP's Climate Forecast System version 2 (CFSv2). Documentation for this system here.

5/April/2019

• An upgrade to MetOffice contribution (change of forecasting system version to GloSea5-GC2-LI) has been introduced from May 2019 nominal start date.