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Global RTOFS Data Access

The NOMADS data server address has been changed. The old address
has been changed to
Please update any bookmarks or scripts that use the NOMADS data server.

Changes were made to operational RTOFS starting with the 0504202100 Z cycle to correct for a drift in assimilation of Absolute Dynamic Topography (ADT) caused by changes in data processing.

Model nowcast/forecast data from Global RTOFS is available as Network Common Data Format (NetCDF) and Open-source Project for a Network Data Access Protocol (OpenDAP) from the following locations:

  1. NCO Production FTP Server (NetCDF)
    latest run only

  2. NCO Operational NOMADS ( NetCDF OpenDAP )
    latest + 1 day archive
    Note: RTOFS OpenDAP on the NOMADS server is not operational at the present time. Full file downloads are still available.

NetCDF and OpenDAP are common data formats and viewers/decoders are available from a number of vendors and organizations.

Data is available as individual NetCDF files, OpenDAP urls, and regional GRiB2 files. Information on the file naming conventions and file contents can be found here:

Note that the NOMADS OpenDAP urls aggregate all of the nowcast and forecast times into two urls (forecast, nowcast) for each type of file (2ds diag or 2ds prog surface files, 3ztio, 3zsio, 3zuio, and 3zvio full-volume data).

For analyzing the model data in MATLAB® we recommend the NCTOOLBOX for MATLAB. NCTOOLBOX can read NetCDF, OPeNDAP, HDF5, GRIB, GRIB2, HDF4 and many (15+) other file formats. The complete list of formats is available here.

Notes on processing Global RTOFS data

The interpolated and native global horizontal grids are very large (3298x4500 native, 14.8 million grid points), (2160x4320 interpolated, 9.3 million grid points). Loading and mapping a single layer of the full global grid takes a considerable amount of memory.

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Page last modified: Thursday, 18-Feb-2021 19:45:48 UTC