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(RESOLVED) Using WRF Output for WRF Initial and Lateral Boundary Conditions

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.


New member
Just noticed that beginning with the v3.9 release of the WPS, the metgrid.exe program is capable of reading native, unstructured mesh output in netCDF format from the MPAS model.

Why metgrid is not able of reading native WRF output to then use it as WRF Initial and Lateral Boundary Conditions?

I know this would be very useful to a great number of WRF users, including me!

Thank you
I believe it would probably take a decent amount of work to modify the code to allow this, and unfortunately we are pretty short on resources right now. There is a way to do this using the NCEP Unified Post Processing (UPP) utility, though I am not familiar with the specifics. You could take a look at their documentation to see if that would help you. They also have a support group to answer any questions related to UPP.
please help me to link the wrfout files of one domain to be used as initial and boundary conditions for the other run. I run geogrid it was successful thn i tried linking the wrfout files instead of gfs files bt i was unable to. So please help me to link the wrfout files and run the WRF. Its urgent as i have some deadlines and need to complete the process. I will greatful.
Thank you in advance.
Hi lstwrf,

Please see the response above your post. There is a way to do this using the UPP program. Please first read through the UPP documentation to see if you can figure it out (, and then if you still have questions regarding UPP, please contact their support group (, as that is not something we develop or support.
Hello everybody,
I have the same problem. And found a script in the FAQ of UPP. The link to UPP FAQ:
And the interesting question with the promising answer:
I want to use UPP to convert my wrfout files to grib1, to be used in ungrib of WPS to initialize another WRF run, is there a control file to do this?

Script from the answer:
Using UPP for creating grib1 data from wrfout files to use in ungrib


Use UPP to process the wrfout* output from your model run to get grib1 files with required fields. Fields are contained within the new wrf_cntrl.parm file.

The new wrf_cntrl.parm can be downloaded from the UPP FAQs page (last FAQ):

Run UPP for grib1 output as normal for grib1 format (*Use new wrf_cntrl.parm file)

wrf_cntrl.parm: outputs 3 different “grids” or files for each forecast hour: ¬
WRFTWO* -- 2-d fields, soil, etc
WRFPRS* -- Pressure level fields
WRFNAT* -- Native model level fields

Email the UPP Help Desk for questions/problems running UPP:
More information on UPP can be found at:

WPS – ungrib

Run the UPP grib1 output files through ungrib use as input for the new WRF run. Requires running ungrib twice with two different Vtables and two prefixes for the ungrib/metgrid. First for WRFTWO* and second for WRFPRS*


>> ln -sf ungrib/Variable_Tables/Vtable.ARW.UPP Vtable
>> ./link_grib.csh /path-to-upp-output/WRFTWO* .

Edit the &ungrib section of the namelist.wps to prefix ‘TWO’

out_format = 'WPS',
prefix = 'TWO',

>> ./ungrib.exe


>> rm Vtable GRIB*
>> ln -sf ungrib/Variable_Tables/Vtable.ARWp.UPP Vtable
>> ./link_grib.csh /path-to-upp-output/WRFPRS* .

Edit the &ungrib section of the namelist.wps to prefix ‘PRS’

out_format = 'WPS',
prefix = 'PRS',
>> ./ungrib.exe
WPS – metrid

Run metgrid of the two sets of ungribbed data TWO* and PRS*

Edit &metgrid section of namelist.wps to include the two prefixes

fg_name = 'TWO','PRS'
io_form_metgrid = 2,

>> ./metgrid.exe

If you make progess, please share :)

Good Luck, Mares