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Re: Problems decoding GRIB2 GFS Ensemble grids

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  • Subject: Re: Problems decoding GRIB2 GFS Ensemble grids
  • Date: Mon, 09 Oct 2006 16:53:52 -0600
Kevin,

The GEMPAK GRIB2 parameter tables use 4 numbers to define the parameter
name.
The 4th column is the parameter template, which allows different names
to be assigned depending on the type ofaccumulation, average, ensemble
etc. used.
Log messages from dcgrib2 under "decode_grib2 -34" about unknown
parameter 
mean that the decoder tables need to be updated (in particular, entries
for ensemble PDTs 1 and 11 in column 4).

Updated g2varswmo2.tbl and g2varsncep1.tbl tables which include the
ensemble entries can be downloaded from:

http://www.unidata.ucar.edu/downloads/gempak/tables/

Steve Chiswell
Unidata User SUpport




On Mon, 2006-10-09 at 21:26 +0000, Kevin R. Tyle wrote:
> I've been attempting to decode the GFS ensemble data from the "new" 
> CONDUIT NCEP ftp directory, as described in 
> http://www.unidata.ucar.edu/data/conduit/ldm_idd/ensemble_files.html#GRIB2.  
> However, dcgrib2 is not able to determine the GEMPAK parameter name, and 
> no GEMPAK grid is created.  I've attached the output from the dcgrib2 log.
> 
> Command line used:  dcgrib2 -v 4 -d dcgrib.log YYMMHHDD_gefs_@@@.gem < 
> gec00.t12z.pgrb2af48
> 
> Any ideas?
> 
> Thanks,
> 
> Kevin
> 
> ______________________________________________________________________
> Kevin Tyle, Systems Administrator               **********************
> Dept. of Earth & Atmospheric Sciences           address@hidden
> University at Albany, ES-235                    518-442-4578 (voice)
> 1400 Washington Avenue                          518-442-5825 (fax)
> Albany, NY 12222                                **********************
> ______________________________________________________________________
-- 
Steve Chiswell <address@hidden>
Unidata