Data Exchange Policy

Member GPCs, RCCs, NMHSs and related institutions which produce LRF data can submit and download data products through the web site.

For data exchange, the Access Request Form should be submitted and login ID/password would be provided by the Lead Centre.

Data Requirements

  1. Member GPCs, RCCs and NMHSs shall timely provide hindcasts/forecasts data through the Web site of WMO Lead Centre for LRF MME. The hindcast data should be made using an operational seasonal prediction system that the participating institution uses for a while for their seasonal prediction.
  2. Date of submission 15th ~ 20th of every month
  3. Recommendations for hindcast/forecasts data
    1. Variables to be submitted (monthly mean & anomaly) Required :
      • Surface (2m) temperature
      • Sea Surface temperature
      • Total Precipitation Rate [kg m-2 s-1]
      • Mean Sea Level Pressure [Pa]
      • 850hPa Temperature [K]
      • 500hPa geopotential height [m]
    2. Output Data Format

      GRIB-2 is highly recommended, but GRIB1 temporarily acceptable.

      This site converts GRIB1 to GRIB2 automatically during the upload process.
      * GRIB1 ⇔ GRIB2 converison tool

      * FYI: NetCDF-GRIB converter is available at

    3. Spatial resolution

      2.5°(lat) x 2.5°(lon) over global domain (144 x 73 grids)

      - Writing order : Eastward from 0° to 2.5°W, southward from 90°N to 90°S;
    4. Temporal resolution

      Monthly mean (average from 1st day through the end day of the month)

    5. Lead time

      0-4 months for seasonal forecast

    6. Issue frequency

      Monthly and/or quarterly

    7. Data period
      • hindcast period : Refer to the SUSLRF document
        (a minimum of 15-years of retrospective forecasts)
      • forecast period : 3 months
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