Error using GFS data from 2016 -- GFS format changed?


I'm trying to do some 72-hour runs using GFS input data from 2016, and I'm getting errors like this:

420:FATAL from PE   420: diag_util_mod::get_date_dif: in variable t2 is less than in variable t1


The run starts fine, but on the sixth hour (always with na=96 in the logs) it encounters this error. Rajesh seems to remember that the GFS format changed around this time, and indeed I can run using 2017 06 01 initialization date, but not 2017 05 01. Is there a utility to convert the GFS data to the new format, or does anyone have code I can incorporate into MR Weather App to allow it to read the older GFS format? I am happy to run two different instances of the model for the two types of GFS input.

Thank you in advance for any help or tips on this, 

-Paddy McCarthy.

Paddy - the pre-processing step in the MRW App has only been tested with the GFS data since mid-2017 (GFS v14 and v15 (from 12z July 19, 2017 to current), also v16 starting next month), so it appears you've found an issue using older datasets.  I will check with the developer to see whether this would be possible.  This is the "chgres_cube" preprocessing step, and it uses a table listing the fields in the input GRIB file, so that might be where changes are needed.  But, I don't know if that's the only change!  ufs_inputdata/parm/GFSphys_var_map.txt