[gradsusr] Problem reading sub-hourly WRF grib files (NCEP code table for 15/30 min records)

[Ivan Toman]

Hello,

I'm having difficulties reading sub-hourly time records from WRF grib 
files in GrADS.

UPP follows NCEP code table for timing grib records - for 15 and 30 
minute records use codes 13 and 14 respectively instead of simple 
minutes. This seems to confuse GrADS (or g2ctl/gribmap, I'm not sure).

What I get as result is that I can read any sub-hourly record as long as 
it is not 15 or 30 minute record. For those, I get undefined grid 
instead of data.

I use this workflow for postprocessing: wfrout >(UPP)> grib1 >(cnvgrib)> 
grib2 >(g2ctl,gribmap)> GrADS

Does anybody know what is going on there?

Thank you in advance

Ivan Toman