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How to derive cloud cover from CLDFRA?

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Dear Sir/Madam,

How to derive total, low-level, mid-level and high-level cloud cover (fraction) from the CLDFRA variable available in the wrfout files? I am not using the ARWpost package. Is there a way to derive cloud fraction without using the ARWpost?

Best regards,
Hi Artur,
You could use NCL to do this. Take a look at the script wrfout_to_cf.ncl (which extracts variable profiles at user-defined levels) and then you'll need to add the CLDFRA variable. Since CLDFRA is available in the wrf output, find another similar variable in the NCL script (such as T2) and follow the way it is coded in the file to create your new variable.
Dear kwerner,

Thanks for your help. The problem is that I am not familiar with the NCL as well. The only way for me to process the wrfout files is to open and visualize the wrfout files through the GrADS. Could you suggest me relatively simple relationship (formula) so that I could apply that in GrADS and extract total, low-level, mid-level and high-level cloud fractions from the CLDFRA variable?

Best regards,
Unfortunately we don't support GrADS. We only have the resources to support the WRF model and its components (including the post-processors that we developed in-house). Perhaps someone else on this forum will read this and be able to help you.