Time zone of CMAQ files

Good afternoon. Does anyone know where/which file I have to look at if I want to check the "Coordinated Universal Time (UTC) " for my CMAQ domain? I am using a 4km by 4km domain covering North Carolina.

By convention, all CMAQ data is already in UTC. Some input data to the emissions model SMOKE is in local time, and SMOKE has means to deal with it (a time-zone cross reference file); see the SMOKE documentation. If you are concerned about daylight savings time vs standard time, see I/O API routine ISDSTIME() which returns TRUE exactly when fed a date&time for which daylight savings time is in effect.