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Rgular LAT-LON grid

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Hi all I am trying to run the ARW on a regular lat-lon grid.
I need to do so in order to try to use fully an init data set with limited size:
My input is
LAT: 34.0 - 50.0
LON: 2.0 - 20.0

I am trying with the following set in namelist.wps

parent_id = 1,
parent_grid_ratio = 1,
i_parent_start = 1,
j_parent_start = 1,
e_we = 400,
e_sn = 440,
geog_data_res = 'modis_30s+30s',
dx = 0.040,
dy = 0.030,
map_proj = 'lat-lon',
ref_lat = 42.00,
ref_lon = 11.00,
truelat1 = 42.00,
truelat2 = 42.00,
stand_lon = -11.00,
pole_lat = 90.0,
pole_lon = 0.0,
ref_x = 200.0,
ref_y = 220.0,

The netcdf output seems correct (see wrfout_netcdf.png) but when I pass trough unipost and copygb the result is a translated grid (unipost_copygb.png)
Do you have any idea where am I wrong?



  • wrfout_netcdf.png
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  • unipost_copygb_out.png
    109.4 KB · Views: 1,161
Hi Francesco,
Try to contact the UPP help group regarding this question. You can find their contact information here:

If you do get this figured out, we encourage you to come back to this page and post the fix to potentially help future users.