I am using WRF python to run thisI am not sure what software package you are using to create the plot. But I guess some NL or python scripts may work for you.
Please see the following websites and hope they are helpful for you:
GeoCAT| Geoscience Community Analysis Toolkit
GeoCAT is the Geoscience Community Analysis Toolkit team at the NSF National Center for Atmospheric Research (NCAR).geocat.ucar.edu