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How to prepare a Vtable for GFS nemsio data?

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Dear Colleges,

I am trying to run the WRF model using the GFS forecasts at full (model) resolution which consists of 13 km spatially and 64 model levels vertically (after major update, 12 June, 2019).

For that purpose I downloaded real-time GFS data in nemsio format from the NCEP server

Then, successfully converted the nemsio files to grib2 format. You can see attached the wgrib2 command output for GFS upper-air (gfs.nemsio.upper.txt) and surface (gfs.nemsio.sfc.txt) data files. In order to run the ungrib.exe I need to prepare corresponding Vtables for the files. You may have prepared similar Vtable files for nemsio converted data, it would be great! Otherwise, could you please help me in preparing the relevant Vtables and finding necessary information for filling the mandatory sections of Vtable, for that I will need to use grib table with the codes for this particular GFS data. I already tried to process the the data using available Vtable.GFS (attached), but it does not work (Name of source model =>unknown model from NCEP).

Best regards,


  • Vtable.txt
    6.6 KB · Views: 61
  • gfs.nemsio.sfc.txt
    6.9 KB · Views: 47
  • gfs.nemsio.upper.txt
    61 KB · Views: 60
Is it not possible to download the data you need in gribbed format, and then to simply use the Vtable.GFS file?

I am converting the nemsio format to grib2 format using the gfsnemsio2grb tool ( You can see attached the wgrib2 command output for the converted grib files in my previous post. However, the grib2 data files are not processed with the ungrib.exe when I apply Vtable.GFS

I understand. I was just wondering if it was not possible to get these files in grib format to begin with, to eliminate the extra work, and increased potential in error.