The Meteorology-Chemistry Interface Processor (MCIP) is part of the CMAQ distribution. It is used in the U.S. EPA Models-3 system for conversion of MM5 output into the Models-3 format and creates meteorological data for the CMAQ Chemical Transport Model (CCTM) processor.

Version 2 of MCIP was developed by the U.S. EPA Office of Research and Development, with contributions from the CMAQ development team. This version uses Fortran 90 dynamic memory allocation so that a single executable is used for any MM5 data set irrespective of domain size and resolution. Both MM5 version 2 and version 3 file formats are supported automatically with the option to process data at time steps that are coarser than the input MM5 data.