John, GEMPAK does not have a general converter from its grid file format to NetCDF. What is the original source of your data? If possible, it would be best to go straight to NetCDF from the original data since some data required by the NetCDF files used by IDV are not part of the GEMPAK data file. Steve Chiswell Unidata User Support Ticket Details =================== Ticket ID: FLG-974902 Department: Support GEMPAK Priority: Normal Status: Closed