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> Steve, > > Thank you so much for your detective work! I forwarded your message > to the person doing the post-processing that creates the GRIB files, and > the surface elevation field was added after the other fields were > processed > (the idea being that computation time is faster by adding the field, > in that > it is unchanging). They should still change the PDS in the file to set the correct date in the grib message even if the data in the grid doesn't change. That would be a couple of bytes to write. > > I was able to split the output into two files as you suggested. I > tried to > use this file separately in GDCROSS to plot the terrain, but I can't > seem to get it to work. Is it possible to use this surface elevation > file > in GDCROSS, even though it contains only one level? You can use GDDAIG to create a new surface hght grid with the correct time from the other file. You can simply set: GFUNC = hght GVCORD = none GLEVEL = 0 GDATTIM = 060423/1200f000 and then give the appropriate time for your other data in GRDNAM such as: GRDNAM = hght^050721/1200F003 Set GDOUTF for your July 2005 file and GDFILE for your input file. Steve Chiswell Unidata User Support > > Brian > > > On Jul 19, 2006, at 9:58 AM, Unidata GEMPAK Support wrote: > > > Brian, > > > > I redownloaded your file and ran: > > % cat wrfprs_ruc13_03.tm00 | dcgrib2 -v 1 -d - YYYYMMDDHH_fsl.gem > > There was one grid in your grib file for April 23, 2006 (aka > > surface hght). That > > was the very last grib product in your file (either your output was > > appended at > > that point, or your last product was coded for that date/time > > incorrectly). > > That information comes from the PDS block of the GRIB product. > > > > If you decoded your data to a single file, then GDATTIM=last will > > find that April 23 > > date as the most recent in the file since it is later than the 2005 > > date. > > > > If you use the file name templates as I did above, you will get 2 > > output files: > > > > 2005072112_fsl.gem 2006042312_fsl.gem > > > > Now, using gdattim=last on the 2005072112_fsl.gem will July 21, > > 2005 f003 data. > > > > Basically, the decoder is behaving properly, as is gdinfo. You just > > need to identify the source > > of your April 23, 2006 grid. > > > > Steve Chiswell > > Unidata User SUpport > > > > > >> Hi Steve, > >> > >> I think I've narrowed the problem down to the setting of GDATTIM. > >> Previously, I was using GDATTIM=last, and for some reason, GEMPAK > >> thinks the file is from April 23, 2006 (from one line that is > >> displayed using > >> GDINFO). The file is really from July 21, 2005, and when I set > >> GDATTIM=050721/1200F003, then I can see all the fields when I use > >> GDINFO. > >> > >> Can you tell me what exactly GEMPAK looks at for the date and time > >> when GDATTIM=last? > >> > >> Brian > >> > >> On Jul 17, 2006, at 3:02 PM, Unidata GEMPAK Support wrote: > >> > >>> Brian, > >>> > >>> This grid size (151,987) is well within the 750,000 defined size. > >>> The data in the file posted below is grib1, with 330 fields for > >>> 2005072112F003. I was able to decode it both with dcgrib2 as well > >>> as nagrib. > >>> Have you tried nagrib? > >>> > >>> I don't know what trouble you are having, so can't give you any > >>> other advice at this time. > >>> > >>> Steve Chiswell > >>> Unidata User Support > >>> > >>> > >>>> Hi Steve! > >>>> > >>>> I tried to use dcgrib2 on a grib file for a RUC 13 km output > >>>> file and > >>>> it doesn't seem to be working properly. Perhaps it is the grid > >>>> size > >>>> (451 X 337)? I'm not sure. I have an example file that can be > >>>> downloaded to test in http://www-frd.fsl.noaa.gov/mab/jamison/ > >>>> test/ . > >>>> > >>>> Would it be possible to get a newer version of dcgrib2 that can > >>>> decode this file? > >>>> > >>>> Please let me know. Thanks! > >>>> > >>>> > >>>> Brian Jamison > >>>> > >>>> > >>>> > >>>> > >>>> Hi Steve! > >>>> > >>>> I tried to use dcgrib2 on a grib file for a RUC 13 km output > >>>> file and > >>>> it doesn't seem to be working properly. Perhaps it is the grid > >>>> size > >>>> (451 X 337)? I'm not sure. I have an example file that can be > >>>> downloaded to test in http://www-frd.fsl.noaa.gov/mab/jamison/ > >>>> test/ . > >>>> > >>>> Would it be possible to get a newer version of dcgrib2 that can > >>>> decode this file? > >>>> > >>>> Please let me know. Thanks! > >>>> > >>>> > >>>> Brian Jamison > >>>> > >>>> > >>>> > >>>> > >>> > >>> > >>> Ticket Details > >>> =================== > >>> Ticket ID: PUL-762311 > >>> Department: Support GEMPAK > >>> Priority: Normal > >>> Status: Closed > >>> > >> > >> > > > > > > Ticket Details > > =================== > > Ticket ID: PUL-762311 > > Department: Support GEMPAK > > Priority: Normal > > Status: Closed > > > > Ticket Details =================== Ticket ID: PUL-762311 Department: Support GEMPAK Priority: Normal Status: Closed