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hybrid_opt in WRF_3.9.1 dynamics namelist

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I am trying to run WRF v3.9.1 with the new hybrid vertical coordinate, which the online user guide says should work with this version. I have recompiled with the -hyb flag (configure.wrf attached). However, when I try to run real with hybrid_opt=2 there is an error readying the dynamics namelist. I also notice that there is no HYBRID_OPT variable in the dynamics namelist when I run with the old namelist and check the namelist.output file. Can you please tell me if there is something else I am missing in order to use the hybrid vertical coordinate?
Hi Aaron,
Can you attach that configure.wrf file, and please also attach your namelist.input file, along with the error log from the run?

Thanks for the response and sorry for the delay! I have attached the requested files in a tar file called wrf.tar but I had to rename it as wrf.png for the upload so it will have to be renamed back to wrf.tar.
ajohns14 said:
Thanks for the response and sorry for the delay! I have attached the requested files with .txt appended to the end so I can upload them.


  • configure.wrf.txt
    23.1 KB · Views: 91
more attachements


  • namelist.input.txt
    4.7 KB · Views: 102
  • namelist.output.txt
    78.1 KB · Views: 66
  • rslfiles.tar.txt
    429.5 KB · Views: 65
Thanks for sending those files.
1) Have you made any modifications to your v3.9.1 code, or is it the pristine "out-of-the-box" code?
2) With the rsl* files you gave me, I don't see any error regarding the reading of the dynamics namelist. Did you see an error specifically stating that, or are you assuming there is a problem since it's clearly not processing that part of the namelist?

I just ran a test using your namelist (mostly - I had to modify dates, grid size, etc. to match the met_em* files I was using), with V3.9.1, configured with -hyb, and I don't have any problem with real.exe. I also see 'hybrid_opt' in my namelist.output file, but I can see that you definitely don't have it in yours. If you have not modified the code in any way, can you try 2 things:
1) decrease the number of processors you are using the run real.exe. We typically only run real with a single processor or a handful, while using many more to run wrf. It could be that you are using too many, and something in the hybrid-related code is pushed over the edge with too many.
2) If 1) doesn't help, please attach one of your met_em* files so that I can try a test with your exact input.