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Categorical Precipitation Types

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Hi All,

I am struggling to get the WRF to output the following parameters:


I am running WRFV4.1.3 compiled using the PGI compiler and using UPPV4 to process the wrfout files. It appears to me that UPP is setup correctly because in the grib2 output there are products for the 3 products listed above, but when I view the data in a program such as Panoply the scale goes from 0 to 0 and all the values are also zero in the array. I was also having issues getting the Categorical_Rain_surface to output as well, but I adjusted the RAINCV and RAINNCV entries in the Registry.EM_COMMON for WRF, WRFPLUS, and WRFDA and now that seems to be working. I get data when Categorical_Rain_surface is viewed in Panoply, and the scale looks correct from 0 to 1. I do not see obvious entries (at least obvious to me) in the same Registry file to adjust for the Snow, Freezing Rain, and Ice Pellets though. Would someone have any idea of what I can adjust to get those as well?

Thanks for all the help!
I'm not very familiar with these particular variables. Can you let me know the exact names (in the output) of the 3 variables you're having trouble with, and will you please also attach your namelist.input file? Thanks!

I have attached my name.input file to the post.

So once I run my wrfout files through UPPV4.0 there are a number of parameters labeled Categorical_Freezing_rain_surface (there is one for ice pellets, rain, and snow as well) that all, except for rain, have no data in them. When I look in the grib2 output the products are as follows:

Categorical_Freezing_Rain_surface that has an abbreviation in the grib2 output of CFZR
Categorical_Ice_Pellets_surface that has an abbreviation in the grib2 output of CICEP
Categorical_Snow_surface that has an abbreviation in the grib2 output of CSNOW

When I was doing a Google search of the problem I came across this post

that indicated if I turn on RAINCV and RAINNCV in the Registry_COMMON that I would get instantaneous precipitation output. That seemed to work for Categorical_Rain_surface, but the other 3 still had no input. I didn't know if there were other variables in one of the Registry, or some other file, that I could adjust to get output for those 3 products.

I hope that makes some sense. Thanks for the help!!


  • namelist_input.txt
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Thank you for clarifying that. I think this may be a UPP issue. I'm not sure what algorithms they use to obtain values for those variables. You should post this in the UPP section of the forum. There is a different team that works specifically on UPP that can hopefully help you.