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CFL error when using WRF with EC Earth data

Hung Nguyen

New member
Dear all,

I am using WRFv4.0 with EC Earth data. The simulation period is from Oct 1984 to Jan 2016. WRF ran normally until 20:00:00 18 Jan 1985 and then stopped due to the CFL error. I have tried the following solutions but none them work:

1) Reduced time step to 10 or even 5
2) turned on w_damping
3) set epssm = 0.9
4) set smooth_cg_topo = .true.

I would be grateful if you could help me solve the problem. If you need any information please kindly let me know.

Thank you very much for your kind support.


  • namelist.input
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    1.6 MB · Views: 5
Have you tried another data type to see if it works? Will you also attach your namelist.wps file so I can take a look at your domain? Thanks!
Dear Kwerner,

Thank you for your response.

I tried ERA5 data and WRF completed the simulation normally (same domain, namelist.input, and simulation period). I attached my namelist.wps for your reference.

Thank you very much for you help.


  • namelist.wps
    808 bytes · Views: 4
Thanks for attaching that. I assume this is still an issue for you since you would like to use the EC Earth data. Is that correct, or are you able to move forward now, using the ERA5 data?
Dear Kwerner,

I need to run 3 simulations with ERA5, EC-Earth and MPI data. WRF only crashed with EC-Earth data. May I ask if input data (EC-Earth) can be a reason for the CFL error? If so, I will replace it with another data set.

Thank you again for your kind support.
The fact that it runs okay with other data types seems to indicate the issue is related to the EC-Earth data. It's unclear what it is about that data that causes the issue, but if everything else is kept the same, except the data type, then that would have to be the problem.