Why is APCP not equal to rainc+rainnc+rainsh in UPP？

[qisionline]

I run uppv4.1 to process wrfout（from WRF 4.2） and get APCP, that is, accumulated total prediction. I checked the UPP code and found that it is equal to rainc + rainnc, that is, accumulated total cumulus prediction plus accumulated total grid scale prediction. However, according to the contents discussed in the following two links, APCP seems to be equal to rainc + rainnc + rainsh. How does UPP treat rainsh? Why not add it when calculating APCP?

rainsh：ACCUMULATED SHALLOW CUMULUS PRECIPITATION
https://forum.wrfforum.com/viewtopic.php?f=9&t=11118
https://forum.wrfforum.com/viewtopic.php?f=9&t=4194

 

[hertneky]

UPP does not read in RAINSH from WRF output and there are no plans in the future for adding this.

You could add this fairly easily using another precip variable, such as RAINC, as a guide in the INITPOST.F routine.

e.g. assuming RAINSH is same units as RAINC...

VarName='RAINSH'
call getVariable(fileName,DateStr,DataHandle,VarName,DUMMY, &
IM,1,JM,1,IM,JS,JE,1)
do j = jsta_2l, jend_2u
do i = 1, im
YOUR_VAR_NAME ( i, j ) = dummy ( i, j ) * 0.001
end do
end do

And then add that to total acc precip:
ACPREC(I,J)=ANCPRC(I,J)+CUPREC(I,J)+YOUR_VAR_NAME(I,J)

You would also need to add the new variable to the vrbls2d section at the start of the INITPOST routine, as well as allocating, deallocating, and declaring the variable as described in steps 1-3 of https://dtcenter.org/sites/default/files/community-code/add-new-upp-variable.pdf. Step 5 also gives more detail on the mods in the INITPOST.F routine. Since you would just be adding this variable to total precip which is already output by UPP, then you would not need to do any of the other steps that deal with outputting a new variable in UPP.

You would then need to rebuild the UPP.