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Seems that we did not receive the standard NCEP GDAS file for Dec 11 12:00 from which we would make N202034612_MET_NCEP_6h.hdf, and that file is the main input to the NCEPR2 process. NCEP keeps 10 days of the GDAS files online, which indicates that the file did not get posted within a 10-day period as we scan their archive every 30 minutes. You should be able to use the 06h or 18h file from day 2020346.