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(SOLVED) FZLEV is zero with AFWA Diagnostics V4.2.1

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Before upgrading to the last release 4.2.1 i used the FZLEV with the AFWA_diagnostics. Unfortunately with the new release all values ​​of this variable are zero. Is there an additional option in the namelist.input or something else in order to get the right value for the freezing level?
Can you let me know the version of WRF you were using prior to your upgrade? I'd like to determine what AFWA-related code was modified since that version. Thanks!
Thanks! Can you download/checkout Version 4.1 of the code and let me know if the problem exists with that version? There was some stuff done to the AFWA files between V4.0.3 and V4.1, so if it does NOT work correctly in 4.1, then it's likely due to these changes. Let me know. Thanks!
Thanks for testing that. It looks like prior to the 4.1 release, there were several changes that went into the AFWA diagnostics option due to memory problems. Take a look at this code commit:
If you look at the changes in file phys/module_diag_afwa.F (click the "split view" in the top right above the file modifications), scroll down to line 777 to see the changes that take place, regarding ice options (which include FZLEV). It seems that only particular microphysics schemes are actually capable of calculating the ice options (specifically schemes that use QC, QR, and QNC.

See 7 Oct post by kwerner (below) for more details.
Thank for this information. I used the "conus" suite therefore mp_physics 8 for thompson scheme, as i had already seen in the afwa module icing was processed only with some schemes i thought it should work. However i have overwritten mp_physics with 28 and rerun wrf, but FZLEV is still to zero. Any other idea would be welcome
Some news after have compiled WRF with -D option i get the following error: SIGFPE: Floating-point exception - erroneous arithmetic operation in the diag_functions_MOD_calc_rh. Attached file rsl.error.0000 if this can help to solve the problem.


  • rsl.error.0000.txt
    5.9 KB · Views: 47
Hi Jef,
Okay, upon further review, it looks like the AFWA diagnostics only works with very specific mp_physics packages:
(4) WSM5
(6) WSM6
(10) Morrison
(16) WDM6
(40) Morrison + Aerosol
(95) Eta New
(97) GFS CG

But then out of those, the icing option will only work with those that calculate QC, QR, and QNC, which unfortunately ONLY leaves option 16: WDM6. I tested this out and I am able to get FZLEV values when using option 16, but none of the others.
Thanks for this answer. I'll check this scheme next week as i'm not available for testing until the end of the week. Anyway i need only the freezing level for the icing option, on the other hand i used the maximum 10m wind speed WSPD10MAX too, then i hope it will be available in this configuration.
I'll keep you inform as soon as i've tested it

Good news everything works fine. Just one additional question, where did you find that only the WDM6 provide the QR,QC,QNC value?
Many thanks for your help
That is great news! If you look in the Registry/Registry.EM_COMMON file, and search for "mp_physics," toward the bottom all the options are listed, along with the packaged variables available for each option. You can see that WDM6 is the only one that lists QR, QC, and QNC variables, out of the options supported by AFWA.