Missing Specific AFWA Diagnostics (WRF 4.1.3, 4.2.2)

[rfritzen]

Hello,

I have been trying to run a high-resolution convective case (~3km horizontal domain) initialized using GEFS reforecast data (I construct the intermediate files using the minimum WRF required variables per the documentation), and while the model itself does complete and I do generate convection in expected locations, I am missing a few AFWA diagnostics that I need for my study (Namely, AFWA_HAIL and AFWA_TORNADO).

The documentation for these diagnostics is lacking as it pertains to requirements to use them, I tried using Thompson microphysics (mp_physics = 8), but apparently, this package does not support AFWA as it does not compute certain Q indices. I then tried using WSM6 (mp_physics = 16), which does compute these indices, but those two variables are still not computed. Other AFWA diagnostics pertinent to convection (IE: AFWA_CAPE, AFWA_CIN, etc) are present in the output.

Any pointers would be appreciated. I have attached my latest namelist, IO_VARS, and ncdump from the first wrfout file to the post here. I can also provide additional information (IE: Input Data, Etc) as necessary.

Thanks!

 

[rfritzen]

Just a quick update from some more digging / research.

Looking at the AFWA diagnostics code:

CALL wrf_debug ( DEBUG_LEVEL, 'Option severe_wx_diagnostics requires: QV, QR, QC, QI, QS, QG, QNG' )

So this is tied specifically to the selection of microphysics scheme (Makes sense for Hail). The big gotcha, is that a large number of schemes does not compute QNG, in fact, only five schemes I see in the registry do so:

package   milbrandt2mom   mp_physics==9                -             moist:qv,qc,qr,qi,qs,qg,qh;scalar:qnc,qnr,qni,qns,qng,qnh
package   morr_two_moment mp_physics==10               -             moist:qv,qc,qr,qi,qs,qg;scalar:qni,qns,qnr,qng;state:rqrcuten,rqscuten,rqicuten
#package   milbrandt3mom  mp_physics==12               -             moist:qv,qc,qr,qi,qs,qg,qh;scalar:qnc,qnr,qni,qns,qng,qnh,qzr,qzi,qzs,qzg,qzh
package   nssl_2mom       mp_physics==17               -             moist:qv,qc,qr,qi,qs,qg,qh;scalar:qndrop,qnr,qni,qns,qng,qnh,qvolg,qvolh;state:re_cloud,re_ice,re_snow
package   nssl_2momccn    mp_physics==18               -             moist:qv,qc,qr,qi,qs,qg,qh;scalar:qnn,qndrop,qnr,qni,qns,qng,qnh,qvolg,qvolh;state:re_cloud,re_ice,re_snow
package   nssl_2momg      mp_physics==22               -             moist:qv,qc,qr,qi,qs,qg;scalar:qndrop,qnr,qni,qns,qng,qvolg;state:re_cloud,re_ice,re_snow

Using one of these schemes produces output as expected from AFWA.

I guess the thing I'm curious about now, is what specifically do we need QNG for? There are quite a few number of MP schemes out there that compute all of these indices except QNG, some even compute other 'QN' indices, but not QNG.

 

[Ming Chen]

Many thanks for the kind information you provide regarding the AFWA diagnostic.
For your question of QNG, please take a look at this paper:
https://journals.ametsoc.org/view/journals/atsc/70/2/jas-d-12-0204.1.xml
Probably it can provide some helpful information to answer your question.