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CFL and Segmentation Fault Error

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.



I am trying to run a nesting model with two domains and I am always getting CFL/Segmentation Fault errors despite including several damping options and reducing the time_step to 3*dx. Out of desperation, I have tried to run only the first domain to see if it's a problem due to nesting, but I got the same error. Can someone help me, please? I don't know where the problem is!

I have attached the rsl.error.0000 file with the namelists used.

Thank you so much!


  • segmentation_fault.rar
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Can you please send a *.tar file, instead of *.rar. Unfortunately we are unable to open a .rar file. Thanks!
Hi kwerner,

Of course! I attach them here directly, if you have any problem, let me know!


  • namelist.input
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  • rsl.error.txt.txt
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Thank you for resending those. It looks like you're running an idealized simulation. Can you let me know which one you're running? Thanks!
So when you compiled WRF, did you compile for the em_les case, or are did you compile em_real, and you're trying to run a real case with LES settings?
When you say you're using "option 9," what are you referring to? Thanks!
Hi! Thank you so much for your reply and sorry for the delay!

I compiled the em_real because I am trying to run a real case with LES settings. Is that ok?
About "option 9" I am referring to the case option.

Again, thank you!
I apologize for my misunderstanding, but I'm still not sure what "option 9" is for a case option. At what stage are you choosing this option? Do you mean when you're compiling WRF, and you're choosing the environment/compiler setting "9?"
Sorry, it is my fault... I was talking about an option I used in another case. In this case I did not use this option about the idealized case used. Sorry!
I first would like to apologize for the delay in response. I took a couple of weeks off for the holidays and am just now getting caught up.

The namelist you are using is seemingly set up an idealized case and therefore you are missing some line items, and may have some you don't need. I'm attaching the default namelist.input file for an em_real case with pbl-les settings. I would suggest using this attached namelist as a starting point and adding in your settings (such as date, time, domain size, time_step, etc.). Try running with that namelist to see if you are able to get past the segmentation fault.


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