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Mike, Since you didn't show what the input to gdgrib was, other than the 3 lines shown below, I can't tell what the problem is- but can only guess that you haven't defined the GRID paramter PDS, vertical coordinate or vriable to be converted to grib. Here is what I am using to create the GRIB products in the FNEXRAD feed in GEMPAK 5.6.D.1: gdgrib << EOF GDFILE = nexr GFUNC = n0r GDATTIM = last GLEVEL = 0 GVCORD = none GBTBLS = ;ncargrib2.tbl GBFILE = $GBFILE VERCEN = 2/60/1/1 PDSVAL = n0r%1 PRECSN = b/0 WMOHDR = CPYFIL = PROJ = GRDAREA = KXKY = r e EOF In the above, I am using the NCAR center (#60) in the PDS block with a subcenter (#26) of 1 to signify unidata. You can use NCEP or anything else. I have defined NOR as parameter #201 in the ncargrib2.tbl (which is included in the 5.6.D.1 distribution). I am using vertical coordinate %1 (none) for the surface. I produce a GRIB using #255 in the gds to be the projection of the gempak grid file itself. You are using CPYFIL=#215 which would produce a 20km grid....very coarse. My national mosaic is ~6km, and the regional is 1km. Gdgrib is the same program that is used to create the HAXA00 KWBC product (10km RCM grid) in NOAAPORT (they use parameter #21 which is RDSP1). Steve Chiswell Unidata User Support On Mon, 13 Aug 2001, Michael W Dross wrote: > > Thanks for the suggestion. On that note. I went to try and convert a .gem > file into a grib with #215 grid resolution in a file. This what I used. > > !/bin/csh -f > # > # This script runs GDGRIB in a loop. > # To change parameters, modify the gdgrib.nts file and issue a > # kill -INT to the gdgrib process. > # > > while (1 == 1) > > gdgrib << EOF > restore gdgrib.nts > r > > e > EOF > > sleep 30 > > > gdgrib.nts > GDFILE = /weather/gempak/composite/20010813_radr.gem > GBFILE = /weather/gempak/composite/20010813_radr.grb > CPYFIL = #215 > > > > > I got a error message Cannot Open File > /weather/gempak/composite/20010813_radr.gem. However it is there and > readable. Any suggestions? > > My hope is that I can make a Grib file every 5 mins that could possibly > sent over the IDD. As we talked about awhile back, if I coud convert > directly into the WSI > NOWRAD format, (I have no clue as how to do that) it could be displayed on > a variety of platforms with ease. > > Mike > > > > > > Steve Chiswell > > <address@hidden To: Michael W Dross > <address@hidden> > r.edu> cc: <address@hidden>, > <address@hidden> > Sent by: bcc: > > owner-wxp5@unidat Subject: 20010813: GEMPAK -> > WXP Grid? > a.ucar.edu > > > > > > 08/13/01 02:41 PM > > > > > > > > > > > Mike, > > You can create a GRIB product from the GEMPAK grid using the program > gdgrib. > Presumably you can make WXP read a grib product. > > Steve Chiswell > Unidata User Support > > On Mon, 13 Aug 2001, Michael W Dross wrote: > > > Hi all, > > > > I was wondering if anyone has tried to convert a GEMPAK grid file (.gem) > > into a file format WXP can read. The main reason I am curious is > > that I have GEMPAK creating a national radar mosaic from all the bref and > > vil's every 5 mins. I can display it fine in GEMPAK, but > > would be nice to display on WXP. Just wondering if anyone has every > tried > > this? > > > > Thanks, > > > > Mike > > > > > > > > > >