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Questions on grid analysis nudging timestep

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New member

I encounterd some questions on how to understand the gfdda_interval_m and gfdda_end_h for grid analysis. If I run a 12h simulation from 00Zto 12Z with 6h interval grid analysis, the gfdda_end_h is set to 12, gfdda_interval_m is set to 360, does it mean that the nudging is conducted at the whole 12 period, so the budget analysis is unavailable for 12h or does it mean that the budging is only conducted at 00Z and 06Z?

With your setup, nudging would happen at 00 and 06 UTC. Once you run real.exe, you can take a look at your wrffdda_d01 file to see the times available. The times are similar to a wrfbdy_d01 file with boundary times at the beginning of each input time period. To look at the nudging times in the file, issue
ncdump -v Times wrffdda_d01
and you should see something like

 Times =
  "YYYY-MM-DD_06:00:00" ;
at the end of the print-out.