[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: CONDUIT LDM 12km Data

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: Re: CONDUIT LDM 12km Data
  • Date: Fri, 10 Nov 2006 13:36:11 -0700
Kevin,

The 12km NAM data are surface/boundary lavel fields, similar to the 20km
#215 grids
which were previously available. These files are not the full 3d files
such as the 40km files on the NCEP servers.

You will find additional pressure level 12km grids in the NOAAPORT
broadcast
(the NGRID feed in the unidata IDD feed) under the headings:
# NAM #218 12km grid CONUS
NGRID   ^[LM].B... KWBE

The NCEP NAM40km files have approximately 615 fields per forecast time.
The 12km grids on NOAAPORT by themselves provide ~231 fields. The
awip12 files from NCEP combined with the NOAAPORT broadcast number 
approximately 340 fields.

Steve Chiswell
Unidata User Support

On Fri, 2006-11-10 at 13:59 -0600, Kevin W. Thomas wrote:
> Steve...
> 
> I see that 12km NAM grid #218 data is advertised on the CONDUIT pages in GRIB2
> format.  I added it to our data collection via the "pqact.conf" entry:
> 
> NMC2  ^data/nccf/com/nam/prod/nam.(.*)/nam.t(.*)z.awip12(.*).tm00.grib2 !(.*)!
>       FILE    /arpsdata2/ldm2/datafiles/eta40grb2/eta40grb2.\1\2f\3
> 
> There seems to be a problem with the data.  The file sizes are similar to 
> those
> of the NAM 40km, so I asked locally.
> 
> Yunheng Wang, our local GRIB guru says:
> 
> >> Yunheng...
> >>
> >> My LDM code to capture what is supposed to be GRIB2 format for NAM grid 
> >> #218
> >> work.  Output is available on the ingest cluster in
> >>
> >> /arpsdata2/ldm2/datafiles/eta40grb2
> >>
> >>   
> >The data is NOT right.
> >
> >The data is indeed in GRIB2 format and they also indeed relate with NAM 
> >grid #218. However, they does not contain the ARPS required 3D fields 
> >that are contained in tiled GRIB files.
> >
> >Yunheng.
> 
> Did I make a mistake, or is there a problem with what is being made available?
> 
> Thanks!
> 
>       Kevin W. Thomas
>       Center for Analysis and Prediction of Storms
>       University of Oklahoma
>       Norman, Oklahoma
>       Email:  address@hidden
-- 
Steve Chiswell <address@hidden>
Unidata